The OWC Mercury Accelsior PCIe SSD is what I use every day (a pair of them actually). Still the best way to put a large SSD faster than any SATA SSD into your Mac Pro, or any Mac with Thunderbolt via the Helios external case.
Dedicate an Accelsior for an Adobe Photoshop Lightroom catalog and watch Lightroom fly in Library mode (keep hi-res high quality previews!), Photoshop scratch drive, HD video processing workspace, or any high performance usage scenario.
Thanks for your articles announcing sales by OWC. The OWC Mercury Accelsior PCIe SSD was on my list as I have decided to stick with the box Mac Pro for awhile.
The 480GB was little small for what I wanted to do with it so I bit the bullet and ordered the 960GB unit. It's great they now have a unit with 2 eSATA connections.
MPG: I use dual 960 GB Accelsior cards in my main workstation. They are the best investment I have ever made in achieving a smooth workflow which is not influenced at all by disk speed limitations. The eSATA ports are a nice bonus.