Free: Contests & Raffles.
Either one, which ever one fits and feels better to you. Honestly, which ever one shoots more accurately. If you don't have either caliber and are buying one, I would choose the 308 in a rifle that fits you so you can use it for elk, bear or moose hunting as well.
308 so we can give you crap about a boring old caliber....Or......6.5 so we can give you crap about being a hipster gun toting man bun....Or either! I own both, think both are plenty capable and for me wpukd be whats shooting well and I feel like toting. In that case I'm going with a 308, I don't have either but kind of thinking one might fallow me home in the future.