Sadlyno one here as answered my initial question of weather I would NOTICE a significant difference. I don't need the info on a heavy barrel. I already know that.
Anyways I'm going to purchase the Tikka t3 camo stainless, have my gunsmith fine tune it etc., add a 20 MOA rail and if needed add foam inside the stock. Then go out and do a lot of shooting. Once the barrel starts to go out on me I'll have a new one a bit longer and a size heavier put on. Then if it's to top heavy just add a bit of weight in the stock to rebalance things.
Now to find the right ammo to match the 1:8" twist.
Simple, a sporter weight barrel will shoot great 3 shot groups but will start to open up after that if shot quickly.Big steel slows that down.