I have never even fired a 318 WR. In fact I bet I have only seen 4-5 of them in gun shops in my life, and never seen a single one in the field.

But I have made about 30 338-06 rifles and I kept 2 of them for myself in years past. I have killed game with them and seen a lot of other men kill game with them. They fire a .338 bullet of between 200 and 250 grains (I used some old Speer 275 grain bullets in one of my own for killing elk)and all I have read of the effects of the 318 is the same as what I saw with the 338-06. So knowing the only difference in the bullets fired from the 2 cartridges is .008" of diameter, I have to assume the 2 shells are identical in the game fields. The 338-06 is an EXCELLENT game killing tool. So I am 100% sure the reputation of the 318WR is well deserved.

With 250 grain bullets both will give MVs of 2400 FPS, I can't see how a diameter difference of .008" is going to be noticed by anyone.
I doubt I'll ever see anyone using a 318 here in America. They are very rare here with brass and bullets being very hard to find and very expensive if you did, American will gravitate to the 338-06 case because.338" bullets are quite common and 30-06 brass is inexpensive.

So I think of the 318 WR and the 338-06 as non-identical twins. They don't look exactly alike, but from what I've read about the 318 and what I've seen with the 338-06 they ACT alike in all ways.