The OWC Mercury Extreme is a Sandforce based SSD, its the same as the Corsair Force, and every dog and his friend who makes/labels SSDs with their name have one, except for Intel and Crucial.
Storagereview.com is an excellent place to look for information on storage ofcourse! :-) as mentioned by Chris_Brown.
The bench mark shown in the link above, confirms what others have said, that there is very little difference between them.
Top SSD disk is currently the C300, then there is the PCIe based SSD's by OCZ and others which is essentially two or more disks without their casing, attached to a raid controller, which in turn will give you x times more speed, some of these are also bootable (on windows!)
I think at the moment you will find very aggressive pricing on the Corsair Force series, so go to newegg or similar and pick out the similar drive and compare.
I know I am planing on using SSD's
Henrik
PS: If you can hang in, Intel will be releasing their 3rd Gen within the next several months (could tell you when, but sooner then later!) considering that current 2nd Gen are keeping up or almost keeping up, with current drives is very encouraging