To answer the question that you didn't post, Gobble: yes, you do have to tune mechanical broadheads. And, to answer Double J's question: maybe he wants to use them for turkey hunting here or wants to go to any of the rest of the states in the US that understand that they work well.
The increased length, alone, over a field point changes the balance of the arrow (specifically the FOC, Front of Center). Today's equipment has largely been able to technologically overcome the changes to where most setups and shooters will not need to change a thing on their equipment, however. Mechanical broadheads are simply more forgiving of minor tuning issues that most hunters' setups have.
