i think you're very wise to ask the question, although it'll probably come down to personal preference in the end and most of answers would be based on that but probably wildly different
Depends what you think you'll be shooting most, over what range etc and whether you plan to put a lot of shots thru it.
Personal preference for me, I bought my uncle .223 Rem 700. A coupla reasons why, it was there, it was really good value and had probably less than 50 rounds put through it, came with a bag, scope and lots of rounds.
For what I want a .223 is probably covering enough bases, I have several hundred acres, not thousands of acres so a bigger gun would be fun but not really practical.
I looked at the Axiom stock and know a few locals shooters with them, personally I think they make an incredibly good looking firearm all up. I did think I might get one with the Howa gear but hadn't picked the calibre at that point. I haven't fired one but I gather they take an aweful lot of kick out of firing...I think it's a little over the top for a .223 so decided to leave it on the wishlist
I think if you're going to use a bigger calibre, look at it. If the springs and mechanism are good for 40,000 rounds, then its probably a good but. But if you only put 200 or so rounds through it, it's a bit of a waste.
I don't need a .308 but if I did truth is I'd prolly go axiom regardless...gee it looks noice hahahaha
I'm really happy with the Rem 700 .223 but it may not suit you at all, if you can trial shoot a few different set ups I think you'll find that more informative then all us arm chair experts giving you our own (biased) opinion hahha
They did have a axiom in .223 locally, but gee you shoulda seen the big heavy stainless steel barrel with it. It was not a light rifle when all was said and done. I think the remingtion I got weighs about 3 kilos from memory...research your weights, after a while, the weight will make a difference and if you end up with a gun you really love to shoot THEN you'll be definitely getting your moneys worth