Green guy is wrong
The green guy should have some crutches or a wheelchair!
WD support told me by eMail that the green drives cannot be used in a RAID1 configuration, since they are for "home users" only. WTF?
I bought two green drives for a home-user NAS, which does not have to be fast, but silent and 24/7 eco friendly. I did not know that there are RAID-incompatible HDDs for sale! Lucky for me the NAS manufacturer implemented a work-around.