I suggest you let the rifle make the decision for you.
Pick the rifle first. See what you like and what really fits you. What is it available in?
If both are available in the rifle you choose, I would take the 7mm-08 due to accuracy, ammo availability, etc... as has been said above.
If the rifle you really like and fits is only available in 280, that would work just fine also. If shooting factory ammo, there really isn't much difference.
