Welcome to AH Here is my 2c...I personally think the .338 win mag is one of the most versatile calibers available for Africa PG hunting and everything in North America as well. It will shoot 250g bullets that hit like a hammer for large critters and you will have the ability to shoot 185g bullets and ballisticlly match the 300 mags for smaller game. A 30-06, ,308, 270, or 7-08 shooting 130-140 grain bullets would then make an excellent second gun. All that said, it you think you ever think that you might want to hunt DG someday and/or big bears then @Buckdog recommendation is spot on in my opinion. .375 HH and 30-06 are an excellent pair and you would be covered regardless of what you do in future.