Ballistic performance?
Knockdown power?
Personal preference? (i.e. I just like the caliber but I'm not sure why)
Ammo availability?
Recoil, or the lack of?
I guess my 1st gun (which was chosen
for me at age 11) was equally weighted on all of the above. It was Remington 788 in .243 Win, & I harvested a 10 pt. buck with it the next year.
When I decided to go out for elk this Fall, I guess I weighted those factors equally once again when I chose a Remington 700 CDL in .30-06.
I would have said the recoil was given more bearing in my choice, since I pickedthe '06over the 7mm Mag (which I've used on Mulies) and the .300 Winnie Mag. Then again, I did choose it over the .308, because I thought a bit of extra reach would be wortha bit of extra recoil.
Naturally, choosing among those particular calibers is pretty much splitting hairs, but you have to make a choice that
you can live with, & let the flamers say what they will.
I also hear what the others are saying about spacing calibers. I've got a pretty good case of lust for a Savage 14 American Classic in 7mm-08, but I've blown so much $$$ on guns, ammo, and associated trinkets this year, that I really ought to "stick to my guns" for a while. The well-reasoned side of me says I'd be foolish to get yet another gun, when the 140's it shoots will be so close to150's out of my '06. Plus, I'm not even planning any whitetail hunts.
But MAN, does that Savage look like it'd be one sweet shooting setup! It appears that I've been bitten by the gun bug!