I've only had it for a couple of days. Today it started on it timer and then docked to recharge. It does a great job cleaning under beds and dressers. It seems to get confused around multiple vertical barriers like chair and table legs. It kept bumping, rotating and trying again until I came and rescued it. The worst failure was having to find it ( with help of the kids) and discovering the on/off switch underneath was turned off (?). May while rolling over a floor register? Bottom Line: It picked up lots of pet hair, dirt and dust. Over all the jury is still put on whether I'll return it or not. Day 3- after deploying on its scheduled cleaning it disappeared. I had to search for it ( no beeps to identify where it was) finally I found in a corner of one of our bedrooms, unobstructed and powered off. I have no idea how far it was into cleaning, but my confidence is dropping each day I use it. UPDATE: After more than a year, it has become a valuable maintenance vac. It keeps the house clean and does a great job where a conventional vac can't go. It's still a random vac- do NOT watch it roam It will drive you nuts watching it roam into the same dead end after leaving an area. All in all, for the money it's a game changer for keeping the house clean.