http://www.macnn.com/articles/13/05/02/offers.alternative.to.fusion.drive.larger.ssds/
Apple adds 256GB, 512GB SSD options for custom iMacs
updated 10:46 am EDT, Thu May 2, 2013
Offers alternative to Fusion Drive, larger SSDs
Apple has added 256GB and 512GB SSD options for build-to-order iMac customers at its online store. Picking 256GB adds $300 to the cost of a system, while choosing 512GB adds $600. Stock iMac configurations are priced between $1,299 and $1,999.
Until now, 21.5-inch iMacs were limited either to a 1TB hard drive or a Fusion Drive, Apple's HDD/SSD pairing. 27-inch iMacs had options for 1TB and 3TB hard drives or Fusion Drives, as well as a 768GB SSD. The addition of smaller SSD options should be particularly useful for 27-inch iMac buyers who need performance but not a large amount of storage.
