I have used them in my 338 Kahn, basically the same thing as your rifle with a different name. It has a 34" 1-10 twist and shoots the 350s very well. I was loading them to 2850 fps.
They also work very well in my 338 AM at 3250 fps in a 1-10 twist.
Saying which will be better in the 300 gr class will be a toss up. In my rifles, the 300 gr ULD RBBT Wildcat shot slightly tighter groups then the 300 gr SMK but you better be shooting at ranges past 500 yards or you will not see much difference.
The Wildcat is a stouter bullet with a heavier jacket.
Where do you live? I may be able to scrounge up some extra 350s to send you to try out if you want. I do not have many left and the ones I have are mainly going to stay in my inventory but I could let a few slip your way if your interested in trying them.
I will say that in my Kahn, recoil with the 300 gr pills is all warm and fuzzy, not so with the 350s!!!
Kirby Allen(50)