Benchmark Reviews posted a review on the OCZ RD400 PCIe NVMe SSD
A quote from the article:
These days, better performance can be achieved with a PCIEx4 SSD in the m.2 form factor, mounted on a simple PCIe adapter card (that you don't have to use if your motherboard has an m.2 slot). Today Benchmark Reviews checks out this modern iteration of a PCIe SSD in the 512GB Toshiba RD400.OCZ RD400 PCIe NVMe SSD Review @ Benchmark Reviews