It depends a little on where you are going and what game you will be concentrating on shooting. I have successfuly hunted Africa with all three. If the 338 recoil is a big issue take the 7mm mag. Looking back over decades of hunting the African continent the plains game rifle choice frankly has not made much difference, be it an 06, 7mm Mag, 338, 375 0r one of my 416s. For example one trip i used a 300 RUM and disliked its recoil so switched to a 300 Win Mag which I found more easy on my body. Have successful used a 25/06 and a 257 Weatherby on plains game. I am a gun nut and like to experiment with different calibers over decades of hunting Africa. Depending on what and where i am hunting i guess my favorites would be a 300 and a 416. Do not not go out and buy new ones, stick with your 7mm mag and 416. I like heavy for caliber bullets feeling they work better on a variety of game. For example, on Tiny Ten animals they zip through and in my experience blow through not ruining hide on the way. Just a few thoughts gained annually hunting hard all over the African continent. More than fifty years.