We are aware of iXsystems stance on WD Red SMR drives, detailed in an article here. The short version is that they advise against use of these drives. That blog was posted after we had already embarked upon this adventure. It says look to WD for more information and WD has not, over the course of the ensuing month, provided an update. Even after it came out we thought the experiment worthwhile since the number of users that read the iXsystems blog is likely a minority, even among STH readers.