The 350's will put a big hole in and out. Years ago a friend had has gong set up at the 50 yd line, 1" thick steel plate. I was shooting 350 gr speers at ~2500 fps out of my Lott. Darn near punched a hole through the plate.
For those who can shoot a Lott from any field position with 500's and ignore recoil, more power to you. I could never ignore the recoil from the 500's. The 350's on the other hand you could shoot from any position and ignore the recoil. I'd also expect better terminal performance on game from the 350's due to the higher impact velocity.
I have a 458 Win Mag in a Whitworth and a 458 Lott in a CZ, that AHR worked over prior to me. The Lott has a 22" barrel and synthetic stock. Why, only because I wanted them. I had a a 458 Win prior to this current one.
I avoided 500 grain bullets in my Win, loved shooting the 400 grainers. I did shoot some 450's in the Win Mag, not too bad, but as much fun as the 400's.
The factory 500's in the Lott, put recoil in perspective for me. They also redefined "fun." A little bit of their fun and my fun-meter is pegged. Though after a round or three of the Lott, the 416's recoil seem very light and 375's almost non-existent.
I totally agree, my hat is off to anyone that shoots 500gr Lott's and can ignore the recoil. My experience is that if I get careless or sloppy with rifle hold, it lets me know Quickly.
If Barnes would only make the 458 in a 400 grain TSX, I would be very happy. And would probably actually use the Win & Lott for hunting at times.
As Eastwood said, a man has got to his limitations; and 500 grains in the Lott exceeds mine for field position shooting. But that is me and not everyone for sure.