The best Philadelphia cheese steak is probably at some mythical place that, for whatever reason, hasn't yet been built.
Seriously what I loved about the Philadelphia area was that there were so many places that offered very good cheese steaks and deli. (I like a good cheese steak but think I more crave a good italian hoagie with sweet and hot peppers.) Is Centrella's on Brookline still around? Not sure if it the best in either category but it sure was good. The meat in the cheese steak was quite tasty.