I know there are many threads all over the inter webs comparing Yosemite vs Snow Leopard on OLDER macs (with the consensus being SL is faster on older macs). The problem is, I simply can't find one thread talking about whether Snow Leopard is faster on NEWER Macs. Its a legitimate question, as the newer operating systems that use more (memory) resources, may change the speed equation by taking advantage of 64-bit hardware. I have a mid 2010 iMac, core i3, 4gb RAM, I need to set up with a new OS. I simply HATE the look of Yosemite, with its 2D 1980's Atari-era design aesthetic. Snow Leopard design was a far classier act, with a better energy. But speed of the user interface is of utmost importance, with future compatibility with apps a distant second consideration. (I'm not app crazy, but I don't know if there's an app I want in the future that won't be compatible with SL). So my question for today is, will Snow Leopard run faster on a system that can easily run Yosemite; ie. a 4gb core i3 or perhaps even 12gb core i5? I need some help making up my mind which system to go with, 'cos I have no plans on changing it after that!