I would chose 7MM WSM just because I like 7MM.That being said I do own a 270WSM and a 300WSM and do not see a spit of difference on game or paper with either.ANY of The WSM`s will take anything in North America and although not legal for everything in Africa,would do the same there.

Its all right to be white!!
Stupidity left unattended will run rampant
Don't argue with stupid people, They will drag you down to their level and then win by experience