I play mostly Italian and Irish folk, so I prefer a good medium weight pic that's pretty small and non-beveled. I tried the Wegens; but, the bevel just got in the way of my tremelo. I rely on the good cheap ol' Fender mando pics that are about the size of the first thumb joint.
I've tried at least ten different styles of pic -- I think it all depends on your style of music, your style of playing, and of course, your instrument. One my mandos prefers a lighter touch than the Fender medium.