Bow-Nut,
My experience with the Spitfires is this........they always open up SOMEWHERE and do the job. I have seen " Bullet Hole" style entrances and almost full width as well so the entrance hole seems to be hit or miss.
They are pretty slow opening up, and seem the majority of the time to not fully open until inside. They are sharp, and tough, but that slow opening and the chance for a high small entrance spooks me away from them.

I want NAP to come out with a 1 3/4" version of their Scorpion........THAT' S the head I would love to see.