However, after chatting with Mike (The Office Maven), it is clear that it is much better to install Windows 10 on the PCIe H.2 NVMe SSD drive because it is much faster than the SATA 2.5 SSD drive. In that blog post I initially installed Windows 10 on the SATA SSD drive which is the one that by default Windows 10 has visibility about before installing Windows 10 with the RST_AHCI drivers for the PCIe M.2 SSD. This post is related to this long and hardware related blog post that I wrote on how to install a PCI2 M.2 SSD drive and a SATA SSD drive in a Surface Studio:
