I have both (not Tikka). The Creed will generally shoot tighter groups than the Swede; both of mine have Shilen barrels, so that should be a wash.
One can reload the Swede and get great accuracy. Factory ammo definitely favors the Creed. The Creed is less sensitive to various kinds of ammo, shoots about everything well. The Swede is more picky, but does great with what it likes. My Swede is a Lapua snob, loves Lapua brass and 139 gr. Scenars over MRP.
Given that choice, to me it would be the Creed, although I really like my Swede. Both are keepers. The Creed will give you more performance with less effort. Their ballistic performance is pretty close. A reloader can push the slightly larger case a bit faster. Critters will never know the difference.
DF
I have a T3 in 6.5 Swede. I have not found it to be picky at all in hand loads but for Hornady GMX bullets. It is the only bullet that seems consistently over 1" groups. I am not a real accomplished shooter and my loads are built with basic reloading equipment and techniques.
Lapua and Privi are true Swede/euro spec brass. Winchester brass is based off 30-06 and a few thousandths smaller at the base.
As mentioned earlier, I would probably just go with the Creed unless you are a reloader.
