The Blackplane is able to handle SATA III Speeds.  Tested with LSI SAS1064E Raid Controller and 2 Crucial SSDs (in Raid 1).   I forgot exact numbers, but they were in range of the rated Read/Write Speeds for the SSDs.
I am trying to figure out if the Backplane "das29rtb4b0" would be able to support SATA III Speeds as I want to add a raid controller to my server.  Any help or information would be appreciated!   EDIT:   The Blackplane is able to handle SATA III Speeds. Tested with LSI SAS1064E Raid Controller and 2 Crucial SSDs (in Raid 1). I forgot exact numbers, but they were in range of the rated Read/Write Speeds for the SSDs.   
BackPlane "das29rtb4b0" throughput (CS24-SC)