Re: .300 WSM decision
Both should easily go SUB-MOA with a tuned handload. I prefer the Vangard because it has a beefier action and a little more weight for stability and absorbing recoil. If you shoulder both rifles back to back, that Tikka is gonna feel pretty light and wispy. A 300WSM pushing a high BC 180-210 bullet at max velocity will generate some recoil. I also prefer the Monte Carlo cheek on the Vangard stock and the recoil pad is decent.
The Vangard's now have a pretty decent trigger that can be adjust down to about 3lbs. The Tikka has an excellent trigger that can be adjusted down to about 2.5lbs. I like a 2lb trigger and for $95, the Timney is an easy drop in on the Vangard.
I have three Vangards, 300WSM, 270WSM, and 7mmRM. On all three, I can load the big Bergers into the lands and the rounds will still fit the magazine. The Tikka, I don't know if this would be an option?
Plus, lets face it, that Tikka is a little funny looking......LOL