The LB3550 robotic lawn mower is  very exciting.  It has the most advanced software of all KA robot lawn mowers.
The LB3550 robot mower covers the widest area of all KA’s mowers: 56,000 sq. ft. lawn area, typically 1.6 acre lots or more.
The super charged LB3550 robotic lawn mower has excellent hill gripping capability due to its extra wide tires.
Advanced Zone Control allows programming Lawnbott to drive the shortest distance to the next zone.
The Smart Spiral feature detects tall grass, providing focused cutting on areas needing more attention.
Zero turn front wheels increase agility.
The LB3500 has the same great features as the LB3550, except its max mowing area is 40,000 sq. ft, or 1.2 acre lots (typical).