I'd go with the .270 if you're hunting deer and smaller game. If you plan on hunting larger game (Elk, Moose, etc.) I'd get a .30-06. For hunting White Tail deer and smaller game, the .270 is more than enough gun. The "win mag", "ultra mag" etc, calibers tend to be too much gun for White Tail and smaller species. I guided a pair of guys who were shooting Jarrett .300 Ultra Mag rifles. This was way too much gun. When we retrieved the game, I noticed the small entry wound and a missing shoulder on the opposite side. This was a waste in my opinion due to not being able to use a whole shoulder of the animal.
Another thing to consider is availability of ammunition. Common calibers like .270, .308, .30-06 and even .30-30 are fairly common. When you use the "specialty calibers" like the "mag" and "ultra mag" calibers, then you may run into problems. There's not a season that goes by where I don't encounter a frantic hunter who is scrambling for ammo because they forgot to pack ammo before their trip. I usually pack a box of each "common" caliber of factory ammo. Though I cannot sell the ammo, I tend to "barter" for a lot of cool stuff (like game meat and favors to be named later).
Hope I was able to help in your decision.
gf