I feel like the decision you're making should be one based off of clock speeds but how much you value lower temps/lower noise, the MSI card is going to be substantially more quiet/cool than the Zotac card, but if that doesn't mean a thing to you, then you should go with the Zotac card. The clock speed bump is marginal, it's not going to see a massive increase in performance (1 - 3FPS)