The only thing the Deebot U2 is good for is choosing a tiny section of your carpet and wearing it thin. The software programming on this thing is useless compared to my previous robot vacuum which was the cheap-as-chips but absolutely brilliant Deebot 600. Tragically, the Deebot 600 is now discontinued and unavailable in New Zealand. You would think the U2 would be superior with its strategic back-and-forth vacuuming, but no. Neither the 600 or the U2 has mapping, but the 600 works on a random pattern and this is infinitely better. My old 600 whizzes around the house going here, there and everywhere in a totally random pattern, but it always covers every last inch of my floor (our house is 132 sq metres). The U2 will mostly go back and forth and it's not even shifting enough on each sweep so it often ends up going back over the exact same path it has just been on.
Because of the U2's fixed pattern, the U2 struggles to find its way out of a room. I have to pick it up and move it from room to room (as other reviewers have said). On the odd occasion that it does find its way through a doorway, it will stay in the new room for a while, but invariably it will wander back into the original room and start that room all over again. It will then complete the whole room again (well, part of it because it only ever does part of a room) because with its back and forth sweeping it has little chance of finding a doorway.
But this isn't even the worst thing. I'm pretty sure the U2 runs the exact same pattern every time it vacuums, so it's doing the same small section every time I switch it on. In two weeks, it has NEVER been into 50% of my house (office, two bedrooms, laundry and half the hallway) of its own accord. It just completely ignores these rooms. I think if I asked a monkey to vacuum my house it would do a better job.
Also, the U2 does NOT run for 110 minutes and hasn't since I started using it a couple of weeks ago. It runs for about 73 minutes (on standard suction). I'm seriously considering returning this, but atm am using it as a ‘second robot’ to reduce the workload for my 600. Trust me, just buy ANY OTHER MODEL. On the plus side, it has 3 suctions levels to choose from and it picks up dust as well as my old 600. I also like that it talks. I haven't used the mopping feature as I only bought it for vacuuming. I would NEVER purchase this again.