I bought this to replace an older model Roomba.  I really liked the idea of the large capacity base.  I have a couple of complaints.  The profile isn't as low as the Roomba.  The  machine doesn't go underneath my couch.  The only other complaint I have is he doesn't handle doors well.  As he is leaving one of my rooms, he hugs the wall and bumps against the open door.  As he turns left to go around the door, he ends up shutting the door and locking himself in the room.  Those complaints aside, I think this machine does a good job.