I shoot 4 blade muzzys also. They fly close enough to my field points that I just adjusted my sights slightly. Last year I tried to get my bow tuned perfectly and I just couldn't do it to perfection. I'll get my setup tuned in a Hooter Shooter machine after the season is over.

If you are getting good arrow flight and accuracy, should use your broadheads only and set your sights accordingly. Messing around with your setup this close to opening day could lower your confidence at the moment of truth.