I like to space it out between both teams. I usually just join who needs more players. The best team consists of a lot more than just weapons. The players, map, and all those things all play a part in the "better" team. For example, if you have ever seen someone whose skilled with garand, you'll know how hard it is to kill them. If the map has a lot of cover, you'll want the .30 cal, while if it's barren you'd want the MG42. Most of the guns are split up between accuracy and rate of fire. Take the rockets secondary for example, you have your C96, which is rapid fire, but only for close range. The Carbine does well at long range but it's rate of fire is a lot slower.