Buying demonstration ex? Lets say that its basically mint. No kids who has spilled soda or any idiots who have scratched it etc. But its been on for like 10 hours everyday or even more? At my local Media Markt they have a Blackbook 2.4 Ghz for the same price as an Alu 2.0 Ghz. It has absolutely no fingerprints and nobody buys Macs at Media Markt, but its been on for like i said at-least 10 hours a day for like 1 year. How does that affect the machine?