I have the cordless electric mulching mower and can say that it works very well. Our yard is normal suburban size tract and takes approximately 45 minutes to mow. I can always mow on a full charge, but need to make sure I keep the grass at a manageable height or else the mower requires additional power. I leave it plugged in the garage and mow - works as expected.
Black & Decker 18" Electric Mulching Mower is recommended by carld