I actually do think of mine as a slave. Proper lazy bastard too, always dodging corners & neglecting certain areas. You have to show them a very firm hand or they'll start taking liberties.

As for OP -- the mop function is really just a damp cloth it drags along behind it. It does work though, it means it picks up even fine dust. But it's not a scrubby mob as in will clean ground-in dirt. Important thing is, take the mop attachment off after it's run or water can seep into the terminals (causing rust) or under the "home" plate (staining the floor).