You might remember Allyn say that Samsung's 850 Pro is the closest to total saturation of SATA 6Gbps. The other option that we have seen is the bunch of SSDs that are attached to a PCI Express bus. HGST, formerly Hitachi Global Storage Technologies, has just SAS'd back (that was a terrible pun… which I refuse to apologize for) with a Serial Attached SCSI 12 Gbps model (pdf link). They claim a maximum read throughput of 1100 MB/s, with 64K chunks, and 130,000 IOPS, with 4K random accesses.
The drives will be based on Intel 20nm enterprise-grade NAND with two bits per memory cell (MLC). Its durability is rated at 25 full driver writes per day for 5 years. Models will range from 100GB, all the way up to 1600GB (1.6TB).
While I am limited to Google Translate, there does not appear to be any price or availability information provided. They are enterprise drives, however, so I expect it to be above typical consumer drives.