I've said it before, and I'll say it again. I've been using a Biscuit for around 7 years now, and NEVER had a vane come off of an arrow! Yes,the Biscuitwill make your vanes wavey, butthey don't effect my accuracy at all. I believe the people that blame things on the Biscuit don't have it set up properly,and or, don't have the cock vane up.
The only time I loose a vane is when I take it off with another broadhead.

Maybe time for you to find a new "pro shop"