iRobot Roomba Combo j9+ robot vacuum review – 1 year of use later, this remains one of the best I've tested and is worth every cen

If you've been wanting a robot vacuum to take some chore time off your hands, you might be curious whether a Roomba, the brand that's almost synonymous with the robot, is right for you.

I've spent around 1000 hours testing 30 vacuums over the past five years, and iRobot Roomba is easily one of my favorites in the robot market. They make some of the best robot vacuums, particularly the best robot vacuums for pet hair that money can buy, but this is reflected in the price tag.

I was given a sample of the iRobot Roomba Combo j9+ back in November of 2023 and I've been fortunate enough to keep hold of it since then for daily use. These are the results of my rigorous, lengthy testing and everything I've learned during this time.

iRobot Roomba Combo j9+: Specifications

Who would it suit?

This robot suits those in small homes and apartments with mixed flooring. It does a largely great job on all floor types and types of dirt, but it's very expensive, so it won't be suitable if you're on a smaller budget.

Setting up the iRobot Roomba Combo j9+

Setting up this robot was the best unboxing experience I've had with a robot vacuum, but it still took a while before it was running. It was a little tricky to wrangle the box upstairs to my apartment, but that's also typical for a vacuum of this size.

Once upstairs, I cleared a space for it and got to work. One of my criticisms is that you need a lot of clearance for the clean base. It needs four feet to the left and one foot to the right. It makes sense – the robot needs to be able to see where it's going – but it's a little frustrating in smaller homes. There's a corner of my living room that's the perfect size for this vacuum, but with the way the walls line up I couldn't place the clean base there. Instead, it's slightly awkwardly in the middle of the wall. It's something that's worth considering when choosing your robot vacuum cleaner; if you don't have this space, it won't work to its full effect.

Once everything was in place, set up took me about an hour. Aside from attaching the mop and putting the robot in its base, there's actually very little to do. The only big thing was filling up the water tank for the mop. But while the instructions were clear, most of my time was taken up with setting up the app.

Again, this is very simple, but there's a lot of hoops to jump through as you have to sign up for an iRobot account. It feels like a way to get my email rather than having any particular benefits, and a decent chunk of the app is dedicated to selling other iRobot products, which is frustrating.

The j9+ then ran a cleaning and mapping run for 39 minutes. The map didn't look quite right, so I then sent it out on another mapping run for 9 minutes. All in all, very easy to set up, if a little long.

What is the iRobot Roomba Combo j9+ like to use?

Over the many months I've been using this vacuum, I've found that the dirt detective function is really useful. It can tell which parts of your home pick up the most dirt; in our case, the entryway is dirtiest. The robot will then give that area special attention, and the map will tell you how long since it's been cleaned and how dirty it's likely to be. You can contrast that with the spots over by the window where there's rarely dirt, or the hallways, which doesn't need as much cleaning.

I've also noticed the robot becoming more and more efficient. The vacuuming runs are less and less erratic. At the start of using it, I found the robot moved in what seemed like random paths as it vacuumed. Now it takes simple, back-and-forth straight lines across the room. That's on top of the keep out-zones, which stop the robot going into areas it shouldn't. I have one for directly under the couch, where there's an extension lead that might gum up the brushroll (see our vacuum jargon buster for any new terms), and on the past weekend I set one for the Christmas tree. The robot will totally avoid these and it's excellent peace of mind.

The iRobot app is fantastic. It's a little slow sometimes and a little glitchy, but largely easy to use. The map is clear and accurate and it's a simple, user-friendly interface that anyone can use. You don't need to be a tech genius for this to work.

Sitting at my desk, it's fairly quiet; it averages at about 50db, which is pretty good for a vacuum, but you won't be able to listen to music or watch TV as it runs. Compared to any of the best upright vacuums or even the best cordless vacuums, this is nothing.

However, by far the worst feature of this vacuum is the noise of the clean base as it empties the vacuum. The automatic dirt removal is fantastic, but when it sucks out the waste the noise gets up to 80db. I promise I'm not exaggerating: it sounds like a jet is taking off. It's loud enough that you can't hear yourself talk under it, and because the base is on the floor and against a shared wall, I'm certain it's disturbing the neighbors. This is comparable to even the latest robot vacuums such as the eufy ones, which all have loud vacuum emptying functions. They don't last long though, around 20 seconds or so.

Test 1: Cereal

For its performance on carpet, I'd say it's 98% of the way there, so for a robot, it could certainly be considered one of the best vacuums for carpet. It's largely effective and the apartment always looks clean after it's vacuumed.

I set it running while writing this review (just in case I missed anything during testing) and I watched it knock cereal into its path and it easily pick it up. Not only was it good cleaning carpet, but it was good on an area rug, too. We have a rug that sheds a lot and this does an excellent job of getting rid of all the fluff.

However, like other robot vacuums, there is almost always something big that it misses; a scrap of a leaf, or a hair, or a crumb. It leaves behind the kind of dirt you would immediately spot and grab if you were vacuuming manually.

In this case, a couple pieces of cereal in the kitchen and the living room, as well as some paper from a notebook. To be fair, it was skirting close to a keep-out zone, but you'd still expect the vacuum to clean right to that edge.

The overall performance is fantastic and it gets most of the dirt, but when you look down and see a big a piece of lint, it doesn't feel that clean. If I know I have people coming over, I still manually vacuum the carpet with a cheap cordless. This is one of the reasons I ask whether robot vacuums are worth it, as I can always do a quicker job myself. But as robots go, it does an excellent job, even if not perfect.

Test 2: Flour and sugar

We test with flour and sugar on carpet and hard floors as a proxy for dust and dead skin.

This robot easily took care of it, clearing a path straight through the sugar and flour, which was most visible on the hard floor in the kitchen. Unlike other robots, none of the dirt stuck to the wheels, so it wasn't tracked through the rest of the house.

There's more on this below but it was especially great that this vacuum could mop the floors properly afterwards, too, as there was no left-over stickiness to the floor. It passed this test with flying colors.

Test 3: Hair

This vacuum is one of the best vacuums for pet hair I've ever tested for hair wrap. My partner has long hair and our usual cordless vacuum has pretty poor hair wrap, so I'm always cutting it out of the rollers. The Combo j9+, however, has two bumpy, silicone rollers that never gum up with hair. It always pulls hair out of the carpet and does a much, much better job that even the Eufy S1 Pro Omni, our current best robot vacuum for pet hair.

Test 4: The mop

This robot also has its own mop. I love this function, as unlike other robot vacuums you don't need to swap any attachments. The mop sits on the back of the robot and automatically flips out for cleaning.

It's one of the most ingenious designs I've seen, as one of my biggest complaints with other models is that you have to swap out the vacuum attachments and fill up the water tank yourself, which defeats the point of a robot mop. Another great design point is that on other robots, the mop sits underneath the vacuum at all times, which then drags dirty water around the house. On this vacuum, it will never drag across the carpet, so everything is always dry.

It definitely makes a huge difference when this mops. I know I should do it more often but I can rarely be bothered to mop the hardwood floor in my kitchen. This robot does it every time it runs and the floor is shinier and cleaner for it. I also love that this vacuum can scrub. Unlike other robot mops, it can scrub at particularly hard dirt and areas it knows gets a lot of traffic. That means hard food stains come up pretty easily.

However, it struggles with getting into corners, which is a little frustrating, and here is where I found the biggest issue with its shape. To be fair to iRobot, that's not something that could be easily fixed, but it struggles to clean around our round trash can. A circle bumping into a circle means that is rarely gets up those small food stains that accumulate as you throw out waste.

iRobot Roomba Combo j9+: Cleaning, storage, and maintenance

Cleaning this robot vacuum is very simple. After more than a month of using this vacuum I haven't had to empty it or refill the water tank once. All the accessories, like a spare mop and the instructions, fit into the handy door in the clean base, so everything is compact and neat. You have to remember to dust the clean base and vacuum occasionally, but that's no different from having a coffee table.

How does the iRobot Roomba Combo j9+ compare?

For a long time, this was the best robot vacuum we'd tested. The suction is as good or better than most we've tested and two features really stand out. The clean base isn't an innovation, but disguising it – or at least attempting to disguise it – as a low coffee table makes this a much more attractive appliance than most.

The other is the automatic mopping. For example, take the Eufy X8 Pro. It's a combo vacuum and mop just like this. However, on the Eufy you have to swap out the mops yourself, and even wet the floor before hand, at which point you might as well do the job yourself.

But when you compare Roomba vs Shark, you can find these same appealing features in Shark's latest models, like the Shark PowerDetect 2-in-1. They also sell for much less than the Combo j9+, even if the cleaning performance isn't quite as good.

And until we finish testing the iRobot Roomba Combo 10 Max, this is better than all other Roomba products, too. It's less aggressive than the Roomba s9+, which we found did a great job cleaning, but often bumped into furniture, and a better job than its predecessor, the Roomba j7+.

Should you buy the iRobot Roomba Combo j9+?

If you can afford it, the Roomba Combo j9+ really is an excellent robot vacuum. Having it perform regular runs of my apartment means my floors never really get that dirty, even if the robot isn't able to pick up every last bit of mess. It really shines in its mopping abilities too, so if your home has lot of hard floors, this is one for you.

I've continued using the Combo j9+ for over a year since I first tested it, and while it still cleans relatively well, I've noticed as the filter clogs up, it's less and less able to pick up debris.

This points to the biggest issue: having to spend money on iRobot parts. You need to replace the bags ($19.99 for 3 at iRobot) and the filter ($34.99 for 3 at iRobot). It isn't that expensive but it's annoying admin to have to buy new parts for your vacuum every so often – most cordless vacuums have hand-wash filters, so you don't have any ongoing costs.

The bonus however of a bagged vacuum is you do not have to deal with any dirt, pet hair or dander directly as it is all sealed up in the bag. If you have allergies, this can be particularly useful and worth the intermittent cost of bags.

All in all, the Roomba Combo j9+ is worth every cent if you can afford it. But if you're willing to part with that much cash, it's worth considering spending a little extra on some of the robots recommended in the section above.

Even with a few snags, the iRobot Roomba Combo j9+ is still one of the best vacuum cleaners we've ever tested.