Your 30-06 is more than enough to harvest the game animals you are after. I went there 3 years ago with my 280Rem shooting Nosler 150gr TEZ bullets and my Kudu and Zebra both taken at about 230 yards went only a few yards. My Impala dropped on the spot. In fact the outfitter lets hunters use his 30-06 so they don't have to deal with customs etc. etc. So that should answer your question.
