I own a 300 Win, and if I had it to do all over again, I'd go -06 (or better yet 7mm Rem Mag or 270 Win). The 300 really shines with 180 or 200gr projectiles. For reasonable hunting distances, the 300 really has little to offer over the 30-06.
That being said, I've made a commitment to myself to learn to shoot the rifle well. I always carry the 300 to every range session with 20 or more rounds, no matter what other rifles I'm shooting. I'm learning how to handle the recoil and my confidence is going up.
