I might be a little biased here, but I would opt for the .300 Win Mag. I say "biased" because I'm having a .300 WM tube put on one of my Sakos right now. I had thought about buying a Kimber .300 WSM, but decidedto have the Sako rebarreled instead.

As far as rifle weight is concerned I personally prefer a heavier gun.Ifind them to besteadier, even on a rest, and of course they lessen felt recoil, which can be a problem when you do a lot of shooting off the bench testing loads.

I haven't checked the prices of light guns versus heavier ones, but if a light gun costs more, I suspect it's because it requiresextra machining in order to eliminate material from the standard version. Extra machining equals extra time and money. I don't think a lighter gun automatically equates to better quality, however.