I'm sorry, I should have been more clear:
In my AR15s, I try to avoid steel case, and only use brass. However, I have heard that steel case Brown Bear works well in ARs. Plan9 uses Golden bear (brass plated steel case) and hasn't had any adverse effects, but that was in low round count, ideal shooting conditions.
In my AK and SKS, anything goes. Usually wolf. It's cheap and the AKs eat it up.
Walt: If you're looking for a fancy replacement CH:
The Bravo Company Charging Handles are the Heat. I fricken love them. It's much easier to get purchase on your charging handle compared to the GI nub.
http://www.bravocompanyusa.com/BCMGU...ndle-s/123.htm
I've used my AR with the large CH for a while, and it works pretty well. Especially when playing with malfunction drills.