What Hoser said. The LR games many of us play are heavily weighted towards long shots from truly screwed up positions. Spotting your impacts is one of the keys to success. The reduced recoil of the 6's is a real edge when trying to stay on target during the recoil cycle, and it comes at a very modest price (if any) in BC and performance in the wind. If I owned two rifles, one would for certain be a 6mm. I'll likely stay with the 6.5's as long as I only have just one if for no other reason than I have all the reloading crap and despise load development. I also think I might someday hunt, and the heavier bullet seems a better choice (like I know beans about hunting!).
Get out and shoot that thing, Scratch. I'm interested to see what is what.