The standard 35 Whelen using a 225 TSX, in the lightest rifle, i.e a Mod 700 CDL, will recoil less than a .375 or 9.3 when both are using 270-286gr bullets, respectively. However, it is wash if you take into account the 9.3 will feel so much like the 35 Whelen you couldn't tell. I agree, the 375 H&H is a different creature. It is a wonderful round, I've also used it here in Utah for elk. for that I had a regular Mod 700 BDL SS, with no recoil reduction just a good Decelerator recoil pad. It was a gem! Way less than a 12ga 3" anything! I had a Mod 700 Classic in .375 that needed a muzzlebrake, but I was setting it up for 300gr bullets for buffalo ( which never materialized, ha) The easiest .375s to shoot, and I mean very pleasant were the Mod 70 synthetic SS, CZ 550 and the Whitworth Express. All a tad heavier than a Mod 700, but not too bad. Any of those three are super fun to hunt with. I especially liked the 270gr bullets ( I used the old, now discontinued, Winchester Fail Safe factory ammo in Africa. I used the 235X and the 300 SierraBT here in Utah for both elk and mule deer.
For the 9.3x62, I don't know what happened, I suspect one rifle had bad headspace. Its no biggy if you train yourself to bolt another in if you hear that horrible "click", ha. I never had a problem with but one 338 WM, which was an early 80's Mod 70 that kicked like a demon, OMG style! I used muzzlebrakes on other 338win, 340W, 338RUM. The model 700 CDL comes with a really efficient recoil pad already, no need for anything else, but I can say the same for any 9.3x62 ( very nostalgic, very useful round too!) So, in my short experience, only the 338s and the Mod 700 classic in .375 benefited from a brake. But, I prefer lighter rifles. My favorite scope is the leupold 1.5x5 VIII., even for long shots. A 9x or so is very handy in more open areas, as said, depends on where you go! I hunted in northern South Africa ( Joberg, Pretoria and east of there and southern Namibia ( Aroab) That part of Namibia looks almost like 50 miles west of me, over in Skull Valley, Utah, ha. Only the plants there all have stickers and thorns!