Roger is a small, round, battery-powered robot which does a great job of cleaning all our floors -- from vinyl kitchen linoleum (when not wet!) through to wooden boards, tatami mats, slate tiles, medium pile nylon and wool carpets.
He will readily cope with any "vacuum friendly" floor, i.e. one which wouldn't cause problems for a regular vacuum cleaner, such as loose clothes, lightweight power cords or speaker wires, sheets of paper, mat fringes and so on. A big incentive to try and keep rooms fairly tidy.
Roger can't do stairs (he's too wide, and hasn't been trained to use climbing rope and pitons), but he will safely avoid falling down them. He has no problem navigating his way around and through the most complex-looking furniture mazes, and will confidently clean under low furniture, like beds.
Because he has a spinning brush at work underneath, he does a significantly better job than straight-suction vacuum cleaners, to the extent that we can set him loose on a floor we've already manually vacuumed, and end up an hour later with a Roger full of dog hair and the like.
Roger generally runs for up to two hours on a fully-charged battery, enough to do a good job of one floor of our house. When his charge gets low, he automatically hunts for his "home base" (if it's on the same floor) and docks for a recharge. A full recharge takes about 3 hours, so he can be turned loose twice or more a day if you're keen.
Pros:
Really does work, leaves floors looking and feeling nicely clean, is rather quiet compared to a regular cleaner, and seems adequately robust. Sure beats doing it all yourself!
Cons:
Darn, we still gotta do stairs and some fiddly nooks by hand, and there's little point in turning him loose on untidy floors, as he'll get snagged on loose clothes and so on pretty quickly. That aside, his main drawback is that you've still got to clean out his dustbin yourself, and the brushes need regular cleaning in a house containing copious amounts of pet-hair, long human hair and odd bits of cotton and wool, rubber bands and the like. In our case, I clean the brushes about every second use, a five-minute task. There have been reports from other users of units which don't work well, or which fail quickly, but Roger has given us no bother and, generally speaking, Internet reports of his cousins have been very good indeed.
Conclusion:
Roger is both clever and powerful enough to do a useful job, at a reasonable price. As a second-generation product from IRobot, who also make mine-detectors for the US Army, he seems to have got over the bleeding-edge stage of product development. Somewhat better than "a toy with a mission!".
Roger is a "Roomba Discovery", bought from Amazon.com, Oct 2004. He costs about $US230, and has $US130 brothers which can clean just as capably. You'll also need to pay for delivery and, since he's sourced from the US, Antipodeans may need a 240v-110v step-down transformer for his charger (about $50).
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