I have shot the spitfires this year and the shock waves too. my first was a doe taken with the spitfire. I had shaky nerves and shot her in the spine. had to finish her off with second shot. however, broadhead and blades were intact with about 7 inch of arrow penetration. the second deer taken was with the shockwave. was a quartering away shot and it blew threw here like slicing butter with a hot knife. she left me with a minimal blood trail (it was a double lung shot entering high from left chest coming out behind crease on right leg). I also shot a deer last year with the spitfire with a huge blood trail anyone could follow. blood spewed every where from instant i hit her. i did not have complete pass thru as arrow entered left chest high protruding out 5 inches right in front of right leg. it was a heart and lung shot. arrow broke off in center. I have used thunderhead 100 gr with blood spewn everywhere with double lung broadside hits. I am almost thinking that it' s not what you shoot at em but where you hit em and where the arrow exits. although the shot on one of my deer this year with the shockwave doesn' t 100% prove the point to me. thanks for all the info, I really enjoy it.