I just want to verify...despite thinking some of the design ideas on iMac's are incredibly stupid (no easy access to boot drive!), I am interested in getting one of the new i5's or i7's. Obviously the i7 is more appealing aside from one huge thing...the BTO nature of the machine. It is my understanding that if I order one of these from Apple, that you simply cannot take it into a store to get serviced if something breaks? I can understand needing to ship it back if it needs a replacement. Fine. But what if it's something that can be opened and fixed? Bad drive, bad motherboard, etc? If someone can help clarify this that would be fantastic. Also, if I chose the i5, are Apple stores able to upgrade the HD in store?