Ming (our MiHome robot vacuum) has been with us for over a year now and, along with a stickvac for handing doormats and hard to reach places, has undertaken all our vacuum cleaning duties. In that time, Ming has spent about 55 hours cleaning and has cleaned 3,112m2 in 113 separate cleanups (about two a week). There have been no breakdowns or repairs required, only routine emptying of the dustbin, and cleaning of brushes and filters (just like an ordinary vac). The spare brushes and filters that we purchased with Ming remain in their box unused and the app says our next filter replacement is still 93 hours away.
Ming's performance is very good, though not perfect. Most of our house is carpet and, like any vac Ming sometimes fails to pick up seeds or other items that have snagged in the carpet fibres. This is common to all vacs, but with a manual vac you have the option of going over the item several times until it either picks up or you give up and pick it up yourself. If Ming doesn't get it on one of her two passes, then it stays until you bring out the stickvac or bend down to do it yourself. It's not a big problem and in a clean of the whole house there might be a handful of items left at the end of the clean.
The other area where Ming is less than perfect is on hard floors with small, hard items. Ming has a small rotating side brush that is intended to push edge items into the cleaning path of the main brush. Unfortunately, if an item is hard and loose, the side brush can skitter it way past the main cleaning brush and into an area that has already been cleaned. Again, I am nitpicking here; it doesn't happen much (unless you spill a cearial box!) and the stickvac sorts it out if I am feeling fussy.
Unfortunately we are, I have to report, rather cruel owners. Ming has her own 'dock' in one of the bedrooms. When she finishes cleaning she is supposed to return to her dock and park. But, if you close the door to the room then, when she has finished cleaning, she will roam the house looking for her dock. When, eventually, she can't find it she will give up and tell you (in a rather plaintive voice) that she can't find the dock. It's a bit like teasing a child or a pet, by hiding their favourite toy, only without the emotional damage. (How immature is that?)
Ming has been a great purchase and if she does breakdown at some point, will certainly be replaced with a later model.