Here is what happened : A colleague from work and I bought two Macbooks, both being plain 1.83GHz C2D Combo Drive. We just needed something portable as our lab already has all CPU power we need. My Macbook did not show a single problem (noise, heat, screen flickering, etc.) that plagued other users. The other Macbook, though, had an issue after my colleague decided to test his OSX media disks. He did a full reinstall with the option "Archive and Install" and right off the first disk he got a message "Media disk is defective. Please replace it and restart your computer". After rebooting, there were no OSX (of course) and he was stuck with a dead Mac. He went back to the Store and they replaced for another one, which I though was a nice way to solve this problem (they argued that it is easier to replace the whole unit than trying to figure it out what is going on). He then decided to test the media again because he is still under the 14-day grace period and it is better be sure everything is fine during this time (the Genius warned him that there were no way to check the media without doing a plain installation) Guess what...the second disk (which contains many Apps) got stuck when installing Garage Band. He tried to reinstall again without Garage Band but it did not went much far. Another trip to Apple Store and he went for another Macbook but now he got a 2GHz C2D model (which has a Superdrive). Ok, now he is wary of trying the media again. I think this Store has been quite reasonable so far but everything has a limit, right ? He did not do anything wrong and he also has all rights to receive a 100% working package. Should he try again ? Cast your vote, please. Be the way, how many of you tried to reinstall OSX ?