Has anyone managed to operate Mountain Lion on a 2009 MBP using a C2D? This is my computer so I'd like some feedback on its performance before I upgrade. I had Lion on my 2011 iMac and it performed terribly so I didn't even bother putting it on my MBP. I'm hoping that Mountain Lion is much more optimised and smooth. Anyone tried it? Any heating problems? Lag? Unresponsiveness? Some comments would be really appreciated! I've searched the forum but couldn't find anything.