OWC now offers a flash drive upgrade (currently up to 480 GB) for the recently launched 13" rMBP: http://eshop.macsales.com/shop/SSD/OWC/Aura_Pro_Retina_2012 Since both the 13" and 15" rMBP are listed on this page I assume they're interchangeable, but I'm not sure. Since this flash drive is compatible with both the 13" and 15" rMBP models, I'm wondering if the 768 GB flash drive offered on EBay can also be used with the 13" rMBP. http://www.ebay.ch/itm/160881976652?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 This would allow us to purchase the standard configuration and potentially save on SSD upgrading. OWC even plans on releasing future flash drive upgrades this month. Would this be a valid option for those of us looking to save a bit with third-party solutions? Apple charges a pretty high premium when upgrading from the base 128 GB flash drive, but I'm not sure if (1) the 15" drives are compatible with the 13" systems and (2) if third-party solutions should be avoided.