The 7mm WSM as about the most versatile, especially considering the available .284 cal bullets available now...that being said, brass is still the hold up. I've owned WSM rifles in .270, 7mm, and .300, but finally got rid of my last one a few years ago. Oddly enough, I still have 4-5x boxes of 7mm WSM and at least 1-2x of the .300 WSM.
