Samsung released performance details on the upcoming 'Z-NAND' enterprise PCIe SSD:
http://www.samsung.com/us/labs/pdfs/collateral/Samsung_Z-NAND_Technology_Brief_v5.pdf
Tom's Hardware article comparing it to Intel Optane P4800X and DC P3700
Nowhere near the write IOPS of Optane, but very low latency that is rather comparable to Optane. According to Samsung, prices will be considerably lower than 3D XPoint, so it probably is a good alternative. 800GB version at first, more likely to follow.
http://www.samsung.com/us/labs/pdfs/collateral/Samsung_Z-NAND_Technology_Brief_v5.pdf
Tom's Hardware article comparing it to Intel Optane P4800X and DC P3700
Nowhere near the write IOPS of Optane, but very low latency that is rather comparable to Optane. According to Samsung, prices will be considerably lower than 3D XPoint, so it probably is a good alternative. 800GB version at first, more likely to follow.