My hubby bought one and a year later decided he didn't like it, I don't think they work that well according to him, plus the idea it has to be plugged in, doesn't sound to safe to me, electricity and a cord, you have to be real careful, he said it was to much trouble.
I have Black & Decker Lawn Hog electric mower purchased four years ago and love it. You do have to be careful of the cord, but I've found it much easier to use, and more reliable than a gas mower. It's very lightweight and does a great job, even if I let the grass grow a little too long!
How big is your yard? If it's huge, and you're going to have to worry about an industrial-type extension cord that'll take forever to roll up again, you're better off with a gas-powered mower. Our yard isn't large, and we've always had an electric mower here. The first one lasted over twenty years (though we had to get a new cord twice), and we're now on our second, and quite pleased with it.