I have all hardwood floors in my house, so I need a good sweeper, not a good vacuumer, and the Dirt Dog is just that. The floors were refinished less than a month ago, so are pretty pristine.The Dirt Dog does an excellent job - it's quite amazing (and disgusting) how much it picks up, even when the floors look okay. Twice it has created a very fine scratch - I know it was the robot as nothing would have been moved across the room in a perfectly straight line. For the most part I have been able to buff the scratch out, BUT I will take a fine scratch over what would be much quicker wear if I wasn't sweeping up the dust, sand, and gravel on a daily basis.