I know nothing of spitfire but I try a new broadhead each year and have found SLICK TRICKS to be the best. They look really small but they go clean through no problem. I have also had really good results with grim reaper but they seem cheap.
Hoped this helps you!

I have used them and killed with then over several years with zero problems. only negative is cost, but arent they all. Good luck!!!

I use the Spitfires Maxx head. Its got the razor tip on head and I use the 100 gr BH with a Matthews Z7 60lb bow. No problems with pass through's.