I purchased the AS5304T Nimbustor model and acquired 4 Western Digital 8TB white label drives, models WD80EMAZ and WD80EZAZ. These models are typically found in WD EasyStore external USB enclosures.
I picked these models because they are 5400RPM 256MB cache and I wanted drives that put out less heat than 7200RPM.
They are white label versions of the WD Red Helium drives (acquired from HGST) with only minor differences. These drives employ the newer SATA standard of having drive reset on pin 3 using 3.3v for PWDIS. Because of this, they usually will not spin up without modification by masking pin 3 of the power connector, or omitting power to that pin (on the older SATA spec, pins 1, 2, and 3, are tied together on the SATA power connector).
Most people who use these drives in an application such as a NAS or server with a backplane, have to mask pin 3 of the drive power connector with kapton tape. Or when used in a PC, a molex to SATA power adapter.
Before attempting to mask the pins I decided to test them in the NAS to check if they would be detected.
I'm happy to report these drives work in the AS5304T without any modification. I suspect it is because the AS5304T uses an external 12v 7a power supply rather than an internal power supply. That, or Asustor supports the newer SATA specification and decoupled pin 3 in the power on the backplane.
I thought it would be helpful to the community to report these findings for anybody considering the Asustor AS5304T or WD white label drives.