For a company which used to only be known as a storage provide for Apple, OWC is really hitting its stride with the PCIe SSD market.  Their newest Mercury Accelsior PCIe SSD family will come in four sizes, a 120GB for $359.99, $529.99 for the 240GB, $949.99 for the  480GB and the largest is 960GB at $2079.99.  If you can’t afford the biggest version then you will love the fact that this PCIe SSD is upgradeable with mPCIe SSDs, assumedly specifically designed for the device.  These mPCIe SSDs use Toshiba 32Gb 24nm Toggle Mode MLC flash with a SandForce SF-2281 controller and you can think of the cards its self as a RAID card; essentially it uses a Marvell 88SE9230 to put the two SSDs into RAID0.  SSD Reviews testing of the 480GB model saw sequential reads and writes hit well over 500MB/s. Don’t expect to boot from this card but the upgradeablilty and ease of installation certainly make this RAID card PCIe SSD combination very attractive.

**UPDATE**  After hearing from an OWC rep, it would appear that this does not suffer from Al’s least favourite attribute of PCIe SSDs, it is indeed bootable both on Mac and PC without even needing third party drivers.  You should probably back up your OS before upgrading the Accelsior though!

"It was only a matter of time before the idea of expandable storage was introduced into the world of PCIe SSDs and, although we have seen a few prototypes in the last year, none have quite made it to market just yet. Our analysis of the OWC Mercury Accelsior 480GB PCIe SSD not only opens the possibility of upgradeable capacity sizes, but also, it just so happens to be only the second consumer targeted PCIe SSD on the market right now and is both Mac and PC ‘plug and play’ compatible."

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