Got the adapter, drive was unformatted, benchmarks look as expected. Tested with my workload, but it looks like I can't hit high enough queue depths to really take advantage of it. Now trying to convince myself of other uses for it (maybe a good time to get into virtualization).
By the way, with HP-branded drives it has been mentioned here several times that you can't get full SMART info (without HP hardware?), and some have wondered how to see total bytes written. The Intel SSD Data Center Tool has a "performance" reporting option (isdct show -performance) that includes DataUnitsWritten, described in the manual as:
"(NVMe Devices only). The number of 512 byte data units the host has written to the device. Value is reported in units of 1000 (1 = 1000 units of 512 bytes)."
Maybe, this is a way to get a partial substitute for missing HP SMART info.
Also, I benchmarked with both the native Windows 10 Pro NVME driver and the Intel one and there was very little difference.
[EDIT: DataUnitsWritten is reported as 1000 units of 512 bytes, not units of 512 bytes. Quoted from the manual.]