Hi Carpediem,
In the past 3 years I have been involved with 9 buff hunts here in South Africa. Three were shot with 375's,four with 458's and two with 450/400. The 3 that were shot with the 375 required at 3 shots each and in one case, 5 shots. A cow that I shot with a 375- the first shot severed the arteries to the heart and it still ran 250m before the 2nd and 3rd shots brought it down. With the 458 and 450, 2 kills were one shot kills and with the others, back up shots killed the buffs before they ran more than 100m-150m. What I trying to say is that, in my opinion, the 375 (also read 9.3) is marginal for all but the most experienced of hunters. The chances are that it can be OK in say 70% of the time, however for that once in a lifetime opportunity rather increase your odds to say 90% by using a .400 up. By the way, I have both 9.3 and 450/400 doubles and in all my hunting life, I have never taken the 9.3 on a buff hunt, only the 450 despite me loving the 9.3. I just don't have that confidence in it.
Regards,
Charls