Without a doubt, white.

But I have to say for me the color of fletching really doesn' t matter much anymore. I have so many vanes laying around right now that I just grab the first pack in the drawer. Currently, this year, I am using 2 purple and 2 black. I just made a few arrows for friend, one set was done with 4 white vanes, and the other set was 2 gold and one black. I have to say that the gold looked better then I thought it would. My wife said that they look like Halloween arrows though. After she said that, I had to agree.