pick a broadhead for the game you're hunting. I use mechanical on whitetail deer, turkey,coyote, and other small game. I use fixed for elk and mule deer!There are some very reliable sharp mech. broadheads available. Sounds like you've got a set up that wull produce plenty of KE to use what ever you choose!
It still cracks me up when mechanical broadheads are blamed for lost deer! Yet when deer are lost using fixed heads, the fixed heads don't get blamed[
]