We have had a low-end Roomba for about 4 years, in a flat with no carpets and no pets. It's brilliant. The ordinary hoover has been banished to the shed and we just have a handheld baby Shark (doo doo doo-doo doo-doo) for corners and ceiling edges.
It is meant to take itself back to the charging station at the end of every run. In practice it does this about two times out of three. So we get home and say "Did Rodney make it back?", and if he didn't, we have to look for him. Note that it is mandatory to give it a name, preferably slightly silly and beginning with R, otherwise the guarantee doesn't apply. 😉
After about a year it died, very suddenly. We called the service centre and after they gave us a couple of checks to do to make sure it wasn't jus tthe battery, they sent a "new" (reconditioned) one of the same series, if not quite the same "710-8xx-14/B" model designation. About a year ago the battery started to have problems charging and we replaced it with a compatible one that cost about £25 and seems stronger than the original.
For our 900 sq.ft flat if we run it three days in a row it will fill its bin 100% on Monday, 80% on Tuesday, and 30% on Wednesday. At that point we assume it has visited most of the floor area. The biggest problem is forgetting to put it on (we are retired, so don't go out and leave the place empty all day every day). Also we have to remember to pick up the bathroom scales because otherwise it humps them and can get stuck.
It seems to work best if you don't sit and watch it. Not really, of course, but sometimes it visits one spot more often than it needs to, a bit like how a random playlist might give you the same tune more often than seems "random". So just let it run, come home, empty the dust, and run it again tomorrow.