Good but with limitations, don't expect miracles.
Good points: Light weight, easy to handle, no cord to fight with. Bad points: Unless you have a small lawn, expect to buy at least four batteries, each pair give about 20 minutes cutting time; OK with shortish dry grass, struggles with longer grass and/or damp grass - you have to mow slowly to avoid the motor bogging down and the batteries overheating. Batteries take two hours or so to charge. Summary, convenient, but not as powerful as a mains mower.