Thanks for the additional information, guys.

500 Nitro: I've been watching both Winchester's Classic Safari Express & Ruger's Magnum line, but for sure I'll watch for the Win. Thanks for the tip. (If you hear anything more about it, please post it here).

I also checked out Savage's 116SE (Safari Express). It has controlled round feeding, and they used to offer it in a number of magnum calibers. But apparently they cut back on the variety - all I've seen it in is 458 Win.