Yesterday, I just bought a shiny spankin' new (2008....) used iMac 4gb RAM, 2.4ghz core2duo. It came with Snow Leopard, and I'm only familiar with Mountain Lion. I want to start with a fresh install of OSX, but I'm not sure which to go with, as I read ML can be installed on an iMac of even this vintage. But I don't know if I should. One, I'm not sure what worthwhile things ML would give me over SL, and what things it would take away that might be good to have in SL (ie. exposé, rosetta....). The major consideration is speed. Some people seem to think ML is faster on the same old hardware, others seem to think SL is faster. It would seem to me that SL would be more optimized for this model and 4gb memory, but I'm not sure? Any consensus on this?