Thanks for your message and thanks for sending the developer report.
Did you try a simple write test, just to check the actual write speed of that SSD?
Generally, the Reinitialise Disk Surface test performs multiple pass overwrites before clearing the data (which is also a write operation) and then read back to verify the sector contents.
So usually if the Reinitialise Disk Surface test is slow, it means that the write speed of the device may be slow.
But this seems really slow, so I'm not really sure if the issue is related to the
- SSD itself
- the disk controller itself which may have some compatibility issue with this device.
Personally, I'd try to connect one of these SSDs completely differently, for example to the integrated Intel chipset controller, just to verify if there is any difference: there is any improved speed in both the "simple" Disk menu -> Surface test -> Write test and also the Disk menu -> Surface test -> Reinitialise disk surface test.