As per title, set up a Elonex Media Center and Hitcahi Plasma for dad XMAS eve, at the moment its running on VGA, I would need at least a 5m DVI cable to run the length. Would there be any REAL benefit of upgrading to DVI?
I doubt you would be able to notice a difference. If you did then it's not likely to be because of the cable, more the equipment at both ends. You could get a short, cheap DVI cable for a couple of quid to try out and if you think it's worth it then get a better 5m one.