I'm a huge 35 cal fan and will attest to the potent lethality of the 35 Whelen and .358 Win. I've never had a .350 Rem Mag (yet!) so I cannot address that cartridge, however, 35 cals with 225 or 250 grain pills rock the boat!!!
Very accurately I might add! I would not feel under gunned if I had to face a large, heavy massed animal, even one with an anti human attitude with a 35 cal handloaded with the right dose of powder with a 250 grain bullet. I guarantee a dead animal!
The Whelen and .350 are virtual ballistic twins @60 fps difference only. No animal would ever know. My .35 of choice these past few years is a custom shop model 7 in .350. It has a 20" BBL, Kevlar stock ( McMilan ) and weighs only 5 7/8 lbs before scope and rings. That rifle is a pleasure to carry and I have as yet needed to fire it more than once at game all the way to moose. Deer just collapse like they slipped on ice and die instantly, same with bears. Before that I had a 760 rechambered to .358 win and it shot incredible groups with 200 gr Spire points but being a conversion I could never get it to feed like I like and sold it. Before that I owned a couple of .358 Blrs. I feel I should also buy a Whelen someday, just becuz