I have never had the feeling the 35 Whelen never caught on. I have read many times articles written by recognized personalities (such as C. Boddington etc.) about hunting in US and there have been praises about how the 35 Whelen do well when hunting moose, hogs etc. Actually I think it is well thought out cartridge with long neck that can swallow long bullets such as 275 or 280 grainers with ease. I think it was an intention when the cartridge was once designed - just heavy bullets for reliable penetration generating moderate recoil. From this point I like it better than the 9.3x62 which has a fairly short neck but fits in standard rifle action. The 9.3x62 is here fairly popular and I wonder how much it spread in recent years in US.
Regarding the 358 caliber my baby is definitely the 350 Rigby Magnum which is perfect with 275 - 300 gr bullets.
For me it is a fine combination for heavy game in Alaska and nondangerous game in Africa.

CZ