Actually I've been using the RL500 as my only lawnmower for 3 years. I
KNOW it works and it works very well. My yard is over 15,000 sqft with
flower beds and trees just like any other yard. The only problem they
have is with slopes. If the slope is over 20 degrees, it'll slip. Other
than that, these mowers are very smart and manage the cut the grass
making it look better than when I used to cut the old fashion way with
a push mower. They're already many thousand that have sold in the
US...in fact search for robomower on ebay you'll see many used ones for
sale.

Check out the website here at:
http://www.robomower.biz for info and videos as to how they work. I was
skeptical too when I first tried mine. Now I'll never mow the old
fashion way again.

Robomower forums:
forums.robomower.biz

forums.robomower.biz to discuss automatic lawnmower