Do you think the GPU for the entry 27" imac is sufficient for the high resolution of the display? Im trying to figure it out, is the c2d stock version enough for me or should I pay the bonus and go for the i5 with better GPU. IMO the gpu update option for c2d 27" imac is quite dumb thing to do cause the price gap after gpu update compared to the i5 version is so small. But I have to draw a line somewhere, so I need to know will I encounter lag or unsmoothnes with the high resolution with only the hd4670 on basic use. with basic use I mean music, browsing, hd-videos, some programming, iphoto etc. Not going to do any video editing. I know that atm I dont _need_ quad core, but maybe in the future that gives my imac a longer lifetime. So after this messy post, what do you think? Is it worth going for the i5 or just be happy with the entry level stock 27" and save some money ?