feathers work but are less durable plus you need to treat them for hunting in rain. i found loading the crossbow in and out tends to wear the fletchings out. i love the look of natural feathers vanes tend to last longer. and i noticed that burning the pattern worked better than stock cut feathers. [all equal] try it you might like them. just get some feather waterproofer if you dont have some allready!
You can use either but find out what is best for your set up. I have a buddy that has a few crossbows and shoots feathers on 2 of them and vanes on the rest. Each has it's own pluses and minuses. Use what you like. Besides, it's fun to play around and experiment with different arrow and fletching combos!