Sim mode is hard on my small SDTV, but I'm working on it. After I get back online I'm going to start working on the transition to only playing Sim mode in dogfights and team battles.
I wish you could make custom game types though, like keep some features of realistic, but turn some of them off. That way you could make a good balanced room if some guys want to play sim, but others aren't quite "there yet".
Also, does anyone else find the handling in Arcade harder than Realistic/Sim? It's a bit strange that.