Will anybody notice a difference? I just ordered the new retina 27" iMac. I got the 4.0 guard i7 and 1tb SSD. I just ordered the base 8gb of ram cause I can steal 8 or 16 from my late 2012 that currently has 24gb. I was thinking of just stealing 8 form that as it would be a more attractive sell for my 2012 to have 16 gb..... Thanks in advance.