I shoot Thunderheads... but I did mess around with 3 Muzzy' s trying to get one I liked. I will say I liked the way the 4 blade assembles better than the 3 blade. IF you' re looking at a 70grain head with that poundage and draw length I think you might be getting a little light in the front end of your arrow. I really think you' d be better served with something above 90...but that' s me.