So I have 8gbs of RAM now, and want to add another 8gb. If I buy 2x4gb sticks, I'll have space to add another 8gb down the road if I need it. If I buy 4x2gb sticks I'll have used up all my slots, but I'll save about $50 dollars it looks like. I plan on having this machine for another 2 years or so before I move up, and want to make the most of it. Will I notice a huge difference between 16 and 24gbs of RAM for things like CS5 and FCE?