Received this two weeks ago and it has worked Fantastic. After charging over night the next day  it made it's first voyage mapping itself and learning our floor plan. It went back over ares I thought it was going to miss. It's like it has it's own brain!! Funny to watch it work its way through the house, as it picks up everything on carpets, rugs, runners, hardwood floors, vinyl floors and it also climbs over threshold strips between various flooring materials. I recommend this to every person who wants to have a cleaning Buddy!!