The SSD Review published a review on the ASRock X99 Extreme11 Motherboard ? Quad X16 SLI/ Crossfire Gfx and 6.1GB/s Speeds A quote from the article:

The ASRock X99 Extreme11 seems to be on par with that of the X99 chip, noting of course that much of the testing conducted here cannot be completed on any other consumer enthusiast level motherboard in the world. Right now, not only is the X99 the only to have 18 SATA ports, but also, it is also the only with 4 included SAS ports along with two M.2 PCIe 3.0 X4 slots.

 ASRock X99 Extreme11 Motherboard Review ? Quad X16 SLI/ Crossfire Gfx and 6.1GB/s Speeds @ The SSD Review