Hi everyone I will be purchasing a high-end 15" Macbook Pro later this month and have several options for purchasing additional RAM; mainly brand (price/warranty/etc which is mostly lifetime anyway), and a 1600MHz option from Kingston. Take your vote! P.S As far as I'm aware - only the high end 15" accepts (and uses) 1600MHz. I've heard there are advantages of memory speed which definitely come in handy with large chunks of video - primarily what this machine will be used for (Film degree + many upcoming LARGE projects). There may be more to numbers though? Seriously guys... your brain doesn't have more memory.