Honestly this gets asked alot. General consensus is get the most mah (~6500-7200) you can and the higher the C the better (to an extent). Anything listed as over 50-65c is not really accurate and will perform about the same as any other.
Turnigy is great on the pocketbook and is actually a pretty decent battery. There are several other companies that offer similiar batteries for more $$. EAM, SMC, Orion, RevTech are all pretty good options.