It sounds like the majority of BTOs (esp the 2.53 models) primarily get the faster 7200 drives...unless you're getting the 2.8 upgrade, the HD is all you can do for the 2.53 since it already comes w/ 4 gb of RAM. Now, if you have your 2.53 upgraded to the 320 gb 720rpm HDD, is the only difference between that and a stock 2.53 the faster HD? Do they build them from scratch and put in the HD, have some models laying around w/ no HD and simply install the 7200 or do they take a stock model and swap out drives? Is there anything else that they do to it? I would think not....so if thats the *only* difference and you need a replacement, couldn't you take it to an Apple Store and do an exchange there? I've heard they will often swap your HD into the new machine you're getting to save time instead of doing a complete file migration. If thats the case why can't they just swap your 7200 drive into the stock one and do the exchange right then & there instead of Apple paying to ship another one over from China (and the customer having to wait). If there's any sort of tweaking that gets done at the factory then that would make sense but I can't think of anything that would be different.