My opinion is that there are WAY WAY too many fixed blade heads out today that will absolutely fly as good or better than mechanicals to even bother with one.

The old excuse of better broadhead flight with a mechanical is out the window.

A quality fixed blade head will never fail to open, it does not use up any energy deploying its blades, they are many times stronger than a mechanical, and they cut a full width hole going in as well as out.