I mostly want to see all of what is out there, but we are playing a mesh of 4th and 6th edition and I have access to 2nd edition, 6th Champions Complete book, and sometimes the 4th edition book (not often tho). I've been thinking about getting the Advanced players guide but they were sold out last I checked.
The GM is very open for what he will let in. Half the time we are even playing with Pathfinder characters too because we occasionally combine groups. However, I have definitely noticed that using a framework or key combination of powers and disadvantages (like equipment) makes a big difference for point economics to be effective.