I think I would try to paper tune my set-up. What you are describing seems to indicate that your set-up in out of time. Either the spine of your arrow or the rest are probably the problem. Are you getting enough rest clearance? Are your arrows too long, the longer the arrow the more weight you need up front. You may get away with field points, however you will not have proper flight regardless of the type of broadhead. I would go back to Gander and ask when the archery manager is there and ask him to check the set-up, the manager generally has more experiance than the regular guys. Hurry up ... the season is almost here.

I have heard of people having problems with Spitfires, opening up with fast bows. One big problem, experianced here in Western New York is that I have witnessed these heads failing to open, verified buy examing entry wounds, due to condensation and freezing once back out in the cold, just like a rifle scope. Good luck!!!!!!