I wouldn't consider it a factor in choosing a type to fly.
Frankly, if the aircraft has had a bingle serious enough to block the exit, it would seem to me that the occupants are likely to be a bit banged up, anyway, and probably incapable of crawling out of the rather small gap available if one was even able to remove a window. The crash axe would be the first attempt at this. It would be difficult. Imagine trying to swing it, upside down, perhaps dazed and confused, without hitting someone.
I'd consider more important factors to be the usability of the aircraft, overall, for the type of training you're carrying out. Which basically comes down to all the ingredients that go into answering the question: which to you find nicer to fly?