The Rook

Hi all,
I'm ordering my Radio today and I have some last minute questions. I'm looking at either the Futabe 6exa or the Futaba 7c. If I am planning on flying park flyers and gas kits with this, does it matter if I order it with the micro or normal set up? Would it be cheaper in the long run to order the standard setup and then buy the micro servos/receiver. What do they mean by PCM mode?

Are there some channels that are better (less common, less interference at the field, etc)

Thanks for all the help! I've learned so much from this site.
J