The best would be to go with the one that drawls your interest the most. As stated before the 270 mag. are worth a look too, of coarse I'm a 270 fan so they get my attention just like 35 calibers and other medium calibers. As I thought this over and skimmed over the other post I was leaning to the 264 Win. mag. (it to has a little interest to me, but have never had one). But then as another has stated the .264 Win. would be competing a bit with your 300 Win. mag. and the 257 weatherby cover a bit more of a nitch. So then I was thinking what are your intended use, if for game up to deer I'd go 257 weatherby, if up to elk go 264 win. mag. That's my opinion. So the best answer is in my first statement. Witch ever you go with I think it will be a grate rifle and you will enjoy it for a long time.