Consumer Reports' lawn-care expert Peter Sawchuk tested two. They don't come cheap. Friendly Robotics RL-1000 Robomower costs $2,000. Lawnbott's LB-3200 Evolution goes for $2,500.
Testers found a safety problem with the Lawnbott that could injure an adult or curious child. Sawchuk says, "When you lift this up, the blade keeps spinning. You can easily reach in and get a nasty injury. If you lift it up further, the blade will stop, but it takes several seconds."
The Robomower doesn't have that safety problem. Lift it up just a little and the blades stop quickly.
The Robomower is designed to work several hours every day or two, trimming off a little bit of grass as it moves about in a random pattern. To keep it in your yard, the Robomower is supposed to turn around when it reaches a wire you lay around the perimeter. And it's supposed to go to a home base for a recharge once its battery runs down. But Sawchuk says you can't just start the Robomower and forget it.
"We found that there were times when it just stopped dead and it actually had to be picked up and physically returned to its charging station. There were other times that the Robomower went outside its perimeter wire and we had to chase it down," says Sawchuk.
Sawchuk says all in all a regular mower does a better job and is a whole lot cheaper.
Last Friday the Consumer Product Safety Commission announced a recall of the Lawnbott after Consumer Reports tests revealed the safety flaw. So far, only one consumer suffered minor cuts from the Lawnbott.
Here's a link for full details on the CPSC recall: www.cpsc.gov.