
My brother had a cheaper robot and it worked really well for him. After looking around a bit I decided to go the more expensive route and buy a Roomba. It's a lot more 'intelligent' than my brother's.
But man, why the hell didn't I buy one sooner?? This thing is brilliant. It has no problems with all the cat hair and litter that's always on my floor. I can schedule it and when it's done it parks itself on the charger. The floor in my apartment only looks this clean just after I cleaned it and that usually only lasts a few hours. Now I can have this thing going each day. It doesn't go everywhere, there's some parts of my livingroom it can't reach. But it moves nicely underneath my couches, where most of the dustbunnies seem to collect.
This thing takes so much effort out of my hands. I'm actually considering getting a Scooba too. Same principle but it mops the floor instead of vacuuming it. Would be brilliant for my oversized bathroom.