I have to use Fusion for XP for a couple of work related programs (quickbooks being one of them). My 24" imac will only hold 4 gb. Along with all the rest of mac programs running, I'm constantly swapping out. Plus the HD is only 320 and had to move media files to external drive. So, I love the idea of having at least 8 gb in the machine, that way I can give Fusion 3 gb for XP (currently giving it 1 gb). Money is not an issue, but it doesn't grow on trees here either. But, I want this one to last (the 24" is only 2 years old). The i7 upgrade is cheap enough, but do I pay the extra for 8 gb of ram (2 x 4 gb) to leave expansion (to 16gb) later?