If you want to play some, try both. That's what I'm doing currently. Rather fun. I'm finding the vanes faster and better for longer distances, larger feathers better for stabilizing quickly on the shorter shots. The vanes perform better off of a raised rest, but I have two longbows on which the rest and striker plate pads are separate, not one piece, with a kind of open slot between them and the smaller vanes seem to do OK out of those two bows. On a regular ledge with one piece leather, the vanes kick pretty badly. Smaller, softer vanes work best if you're not going to use a raised rest. Experiment... it's all interesting. I would add something to your backstop, though. Even the vanes will suffer wear and damage. I use large burlap bags I make myself and fill with plastic sheeting from whatever sources I can get it from... boatyards, furniture stores, etc. Then when centers start to allow too much penetration, you can just stuff more in.