I think .264 Win Mag is about the limit in terms of practicality in that caliber. Much good can be said of the 6.5-06 and its AI offspring, too. To me the .264 reaches just about the point of diminishing returns, but that's purely subjective. If a guy wants a 6.5 powered by 120 grains of powder, then he should have it. If he likes the little .260 Remington then he should have that. Between 6.5-300 and .260, I think I'd choose the .260. Maybe if I was 5'5" I might want the Weatherby.