RE: .308 and .270
I have used both here in Maine and believe that there is so little difference between the two that I doubt anyone could tell. I prefer the 308 just because I like the bullet selection avalable. I might be inclined to pick the 270 over the 308 if longer shots were the norm rather than the rule but even then, the 308 isn't half bad. Pick the one you like best and happy hunting.
I find the Cedar Knoll study interesting and while it may be "just the facts" I'm not sure it is a complete picture. I admit that the study shows that shot placement is the key. If you look, deer shot with a 243 traveled, on average, the furthest while deer shot with a 25 cal. traveled the least distance. I'd like to see a study, I know this can't be done, that takes into account northern deer, public land deer, and bigger animals.