Slammer is spot on. I have a BRNO 375 H&H that I took to Africa last May on a plains game hunt. Just got a CZ 416 Rigby for a buff hunt in 06. I plan on taking the 375 as back-up. For a one gun battery I would go with the 375 H&H as you will have "all of your bases covered". With regard to brand, I highly recommend the CZ's or a BRNO if you can find one. As Slammer indicated, you will need to do a little work on them for dg use.

460 wby mag custom for under $3K. I know it's not what you asked for but...it's a very good deal, octogon barrel and all. If you were builting the same one, getting it built correctly would probably cost well more than double the asking price.

I believe that either the M70 or the CZ in .375 taken from the box to a good smith for tuning and honing is all the gun you need for the whole world. Now how many others you want is a different subject. Yes, any of the 40 bores will give you a theoretical edge on the single buffalo that you will shoot on safari, but only an edge. So long as the beast is fairly unaware of your presence, or at the very least unalarmed, I seriously doubt that you will notice any particular difference in killing power and the .375 is a lot more comfortable is lighter rifles. Frankly, I am unable to give any decent explanation for the battery I keep in my safe. I should sell them all and just keep the Whitworth .375 and use the money to go hunting . . . with the Whitworth. If you can find one of those on the used gun market, grab it. They are accurate and shoot fast, for reasons no one has adequately explained. It's all you need. Go hunting, not gloating.