I had my first Hell-Burger two weeks ago; au poivre, white cheddar. Pardon the pun but holy cow! Best burger ever.
I spent the next week dreaming about another one. The second one (diablo, amish cheddar) was a little overcooked but still really, really good. I'm trying to figure out a way to get back there this weekend...
For the record, I don't eat a lot of red meat. If I eat it too often or too much at once it gives me gout. Very, very painful but I'm willing to risk it for one of these burgers.