That hunt was way back in 2006.
I took my .30-06 for two reasons. First, it was the most powerful rifle I had at the time and I was a pretty good shot with it. In addition, my PH advised it was a better choice for Africa than my then (and still) personal favorite - the .270 Winchester. Watching how far the blue wildebeest I mentioned in my previous post ran after a decent hit, I can affirm that he was right - a .270 wasn't the best tool for the larger plains game.
As for a .375H&H being my choice next time around . . . Well, that trip will include buffalo and .375H&H is the starting point. Second, although I've got a .416 Rem and a .458 Lott in the safe, I shoot the .375H&H much better.
But, if I were going back for just antelope, I'd now probably reach for my .300 Win Mag if I were in an open area. If I were going to an area with thicker cover, I'd probably use it as an excuse to buy a .35 Whelen!