i have shot both. i have shot 4 inch vanes, 2 inch blazer vanes, and 4 inch feathers. feathers have a lot of flight advantages over vanes, but for hunting and ease of use, you cant beat vanes. for target shooting, i would use feathers. they stabilize the arrow just a little more, adn that tiny bit more can be the difference between a good shot and a great shot target shooting. but for hunting, vanes stand up better to the elements and rigors of being hauled around in the truck and through the woods. plus, the accuracy difference really is nearly impossible to notice. i now use 2 inch blazer vanes, and they work great. fixed blade, mechanicals, field tips, they work great for everything. i like the 2 inch vanes over the 4 inch because they are stiffer and tougher. 4 inch vanes are a little softer and warp after a lot of shooting, but the 2 inch vanes dont do that. at least i have not had that problem, i guess i can't speak for the whole world.
if youre having trouble hitting your vanes and ripping them, shoot at different spots. i never shoot groups anymore, i shoot each arrow at a different spot. shooting groups just gets you wrecked arrows and vanes. sure, tight groups look cool, but how often do you shoot groups into a deer? i treat each shot like its the only shot, and shoot at a new spot on every shot. helps me focus on keeping every shot as good as possible without worrying about wrecking the other arrows.