My son and daughter-in-law gifted an iRobot to me for Christmas. I have a bad back and vacuuming is a real strain. This is, IMHO, the most useful appliance in the house after the refrigerator. I live in a 2400 sq ft rancher with carpet (living room, family room, bedrooms), vinyl (kitchen and laundry room), ceramic tile (bathrooms), and flagstone (foyer). Clive the cleaner (I've named him) roams all over the place for a couple of hours and I love it ! I did have to come up with a sneaky way to prevent him from getting trapped under the front edge of the dishwasher though.