people here on the forum will argue back and forth, but in the end, MSI and sapphire are basically the two top partners for AMD cards and the two cards are just about equal. if you like the sapphire one better go with that one
you won't be the first to spend $6 extra for aesthetics lol
I agree with everything vmem has said. I don't think you could go wrong with either one. Sapphire does however provide a lot of 'extras' with their cards far as special connectors and such. I personally have never used any of them. I assume that is why XFX does not even bother to provide them with most of their cards. I 'think' MSI may have some extras too but not sure how much. Their Twin Frozer Cooler is awesome.
I think you are going to have to flip a coin on this one. Or just make a personal decision on which would you feel would look better in your case since they both perform at similar levels.