The question is what you intend to do with it. If you really want to compete in long range rifle, then the 6.5 Creedmor is a great cartridge for that. But if you want a general paper puncher and are not a reloader, then .308 Winchester is obviously more easily found.

The 7mm Remington Mag is going to punish you more on a target range. But is a great elk cartridge.