For many years I contemplated rebarreling my Interarms MkX into .35Whelen. I often read great things about it.
However, when I got around to actually doing it, I went with the .338/06. It's a great caliber and lives up to it's hype.
However, I too like the "wallop" that I get from the .35's. I eventually ended up with a deceased friends .358wcf. It's "close" to the .35Whelen, so now I've got "both", sort-of.
If you live where you're likely to get 200yd+ shots, definitely go with the .338/06. If you hunt wooded areas (like I typically do), then the .35Whelen will not leave you wishing for more.
However, I found my self "missing" not having a .30/06 in the "inventory", so I ended up getting another '06. The only thing wrong with the .30/06 for the lower 48 is that its..."boring".... It just works...
I also latched onto a used Ruger M77MkII in .375Ruger. The .33's and .35's don't get hunted much anymore. The poor old .35Rem hasn't been deer hunting in 5yrs now.... I'm still trying to "hunt" the "new" off of the BLR. Haven't taken a deer with it yet... And Nosler just introduced a 200gr Accubond bullet. Should be just the bullet for the .358 and .35Whelen for non-dangerous game. For heavier game, I'd use the 225gr Accubond.
If/when I go back to Alaska, the .375 will definitely get the pick.... It doesn't kick that much more than the .338/06 and has a bit more "horse power".....
I do see routinely 2,800fps with a 200gr bullet from the .338/06. My "heavy" load is either 58.0gr of IMR4350 or 61.5gr of RL19 under a 250gr bullet for about 2,550fps. Or, about 100fps behind the .338winmags I've chrono'd. There really isn't that much difference between the .338/06 and the .338winmag, and since my '06 holds 5+1 rds, I'd pick it for a "bear" rifle. But, again, the .375Ruger trumps it....
But, it's really easy in my neck of the woods to find a used .338winmag. I doubt you'll have much luck finding .35Whelen ammo, .338/06 ammo, or even .358win ammo, and especially the .375Ruger, in the "boonies"... whereas .338winmag or .375H&H ammo is prevalent. So, with the cost of rebarreling a rifle factored, I'd suggest just finding a used .338winmag.... after you've rebarreled to .35Whelen...... Then, you can decide for yourself "which" YOU prefer...