I often get feathers that are on special. I have both clamps for my Bitz jig. I've fletched both right and left helical and left helical. There's no difference between them so I shoot what's on sale. Last batch I bought was 4" black Trueflight, 100 for $2.
It doesn't matter whether I can see the fletch or not. I know where the arrow is by knowing where my pin was at release. Some of the best shots I make are those that I never saw going.