I have never shot Spitfires but a friend of mine uses them and loves them. I can tell you he took two nice bulls on our Caribou hunt this year and them heads did some incredible damage. I have been bowhunting over 25 years and have never seen broadheads open a animal up like these.

Heres a look at one of his bulls
http://i108.photobucket.com/albums/n14/MatthewsMQ1/DSCN0704.jpg

http://i108.photobucket.com/albums/n14/MatthewsMQ1/DSCN0703.jpg

This bull was taken at 43 yards and didnt walk one step.