You also want to look into how much weight you are going to allow for the battery. There are packs with 2/3AA, AA, 1/2AAA, C, etc. and you need to figure the weight thing out. Look at Great Planes for your batteries and speed control. I have a C-10 and havn't had one problem with it. Also, I would get a peak charger if I were you. It will save your batteries in the long run and give you the most out of your pack.