Are they any good?
It really depends on what you buy and what your set up is. So not sure it’s a straightforward question to answer.
I bought one only a few weeks ago. I bought one and it went over and over the same bit of carpet (Deenkee 4000pa). Thar was on a systematic mode. It didn’t map the rooms. I ended up getting a refund. I want one so I can schedule it up clean and leave it. I couldn’t do that with that one when it only went over one-tenth of the carpet and went over the same but over and over (presumably until it ran out of charge). You had to empty it each time too. The random mode for that worked better and covered more of the room, but you couldn’t schedule the random mode and it clearly was random so not sure of how good of a job it would have made. It had a remote control which was good though plus control through the app. It was £130.
I bought another (price tag £350 - Airzeen 5000pa Pro Q2) once I’d got the other one refunded. The second one is far better. Before you do anything you open all the doors and let it map the entire floor (or can do in bits if you’ve got a step on a floor). You can have multiple maps. Downstairs and upstairs for example. I have three maps currently stored. I’ve just taken a photo of where I’ve plugged in the charger on the other floors. Once mapped, you can just schedule it to vacuum or vacuum+mop. With the mop, mine cannot find its way home if it has the mop attached so I need to be on hand to take the mop off so it can dock. I suspect it’s because I have the dock / charging station on a carpet. It recommends a hard floor.
You have got to bear in mind where to put the charging unit. It needs half to one metre on either side (depending on model) and a couple of metres free space in front too. It needs to be flat against a wall and obviously be near electric. Ideally on a hard floor too. I don’t know how problematic it is if you put it somewhere not fulfilling these conditions. I found this problematic to find a good place for it where it wasn’t in the way and could get in and out etc. It moves around a far bit after it cleans sometimes getting lined up so it can dock properly so I can see it does need space. Mine cannot be under a (normal) radiator either as it is about 30-40cm tall as it has a dust bag in the charging unit that it can deposit the dust from the robot into.
It does a reasonable job but does miss the odd bit. Also cannot get under tables, in gaps, behind doors and up stairs so you’ve still got to do sine vacuuming yourself. Most of them appear to have a mechanism so they don’t fall down stairs (mine doesn’t). It empties the dust into a dust bag so don’t have to constantly empty the robot although it’s really noisy (and schedule it not to do that though or have “quiet” times so it only empties it outside those specified times).
Mop function isn’t great. I can see it’s been over the floor but it doesn’t scrub the floor so if there are stains it probably won’t get them up.
Once it maps the whole floor, it defines different areas as rooms. They’re not necessarily right though but can edit them easily enough and then name the rooms and assign “no go” areas (eg where cables or lego might be) and also “no mop” area for rugs on hard floors.
You can schedule it to vacuum or vacuum and mop specific rooms (including multiple rooms) through the app. Timer is really accurate. You then get a message that it’s started, finished, got stuck, is charging etc. There is also a zone mode which you can use if you spill cereal all over the floor for example, or only want part of the room vacuumed.
I don’t have pets but can see dogs or cars might be wary about it! I daren’t try it when we are all out in case it sets off the burglar alarm.
My carpets and hard floors have never been cleaner!