I've had a Roomba since the first generation came out. I on my third one (R2) but that's cause I wear them out. I have all tile floors and buy my door and area rugs with R2 friendliness in mind. I've never even thought of turning him loose in my studio. Way too many things too worry about. I've always told people that you have to consider it like a toddler and if you prepare your rooms accordingly it's smooth going. I actually had to catch and turn him over one time to spit out a quarter he swallowed. He had broken through his wall and was working around my slot machines so it was a given what was making the racket.
If you want instant gratification it will drive you silly, but if you want to be able to sew while you are doing "housework" it doesn't get any better.