We have an iMac late 2009 i7 2.7 fitted with 12Gb Ram. How much faster would a new 2012 be? we have 3 user accounts running and on my account I have a VMware windows machine and my wife uses Photoshop on her account quite a bit. So potentially quite a few apps open and the machine does beachball a fair amount. What kind of real world increase would we be looking at? 30%? 50% We might have a home for the old one so I am weighing up options now.