RE: .270 or 7mm-08?
First thing I look at are comparable balistics. (No sense in comparing a .22 with 30-30) These two are very close using Federaals chart and the 140 gr Nosler accubond. The .270 muzzle velosity is 150 more FPS, and about 3" higher at 400 yards. (slightly flatter).
That being "equal" . . . I then consider things like ammo availability, re-sale, recoil, etc. I don't roll my own, so when I see that Federal, for example, shows 10 .270 carts to choose from and only 4 for 7mm-08 in the "Premium Vital Shock" section, I'm thinking .270 works for me. Nothing worse than hunting in south bumf*!^k WY and need some more ammo. Your local sporting goods/appliance/furniture store is therefore more likely to have some kind of .270 and nothing in 7mm-08's!
They are both great rounds. I have harvested big game with both (elk). The 7mm-08 does have slightly less kick with the same weight bullet.
I guess I talked myself into the .270.