A lot depends on what kind of rabbit you are after. They all aren't made equal.
For midwestern and rocky mountain cottontails I've always had great success with regular steel blunts, rubber blunts and Magnus blunts sans bleeder.
The little desert cottontails of south Texas are tougher than nails. I have killed a pile of them with blunts also, though a small bladed head can be more dependable.
I head shoot all rabbits when possible.
Snowshoe rabbits give it up pretty easilly to a steel blunt or bladed head.
Jackrabbits always require a broadhead and sometimes several.