Thought i'd add my two cents to this topic. Yeah, I like Tony Luke's. I also like Jim's as well.
Personally, I love the cheez whiz on the cheesesteak- if not slathered on too thick, more spread on like butter, it tastes great. I want to recommend Abner's. It's a little more dumpy, located near UPENN. You can even buy 40's from them.
Their cheesesteak is pretty greasy but really good. I would also recommend their waffle fries topped with melted whiz- so wrong, but so good.