Hey guys, I'm new on here and it looks like you're all clued-up on Mac related stuff so here goes: I'm looking to by a new iMac, specs: 27" 3.4Ghz Quad Core i7 16Gb Ram AMD Radeon HD 6970M 2Gb 1Tb Hard Drive But...I've been offered this from a private seller: 27" 2.8 Ghz Quad Core i7 8Gb Ram ATI Radeon HD 4850 1Tb Hard Drive I've bolded the differences above. Does anyone with experience editing 1080p video in FCP and using After Effects have any advice on buying? The second machine is just about a grand cheaper and I can upgrade the RAM to the full 16Gb, just worried about the graphics card and the slight processor difference. How big a difference in terms of speed/editing/rendering is this? Thanks in advance!