I had one for a while, but I was never happy with it, the food always turned out dry and it was a pain to clean. I find it easier to just cook in a pan on the stove. For less than the price of a George Foreman grill, you can buy yourself a good quality cast iron grill pan that will last forever. Your food will taste better, too.
That's funny because we have just the opposite. Well, I can't compare to the cast iron because we are not suppose to use one with the glass cooktop. But burgers come out juicer on our George Foreman than any other way of cooking for us. We take things out as soon as they are done though. If I did not watch it closely I can see how things could get dry. We have that problem with our regular grill.
The only complaint I have is cleaning it. I clean it well after each use. But it is a messy cleanup. Everything comes off if you clean it right away.