RE: which mechanicals?
I have tested a good many mechanicals and their are some great ones floating around. The rocky snyper is an excellent head as are the rocket steelheads. If you don' t mind shooting a 125 grn head, the steelhead 125 is one of the best broadheads I have ever tested, fixed or mechanical. It penetrates like a fixed blade head, is very durable, and shoots great. The 100 grn version is also very good, but not as tough. The Rocky snyper penetrates as well as the steelheads and has stronger blades, but the ferrule is not as strong. I think you would be happy with any of these three heads. Of course their are others, but these will give you mechancial accuracy with fixed blade penetration.