To be quite honest, after the fiasco that the preclear plugin has been since day #1 I don't believe that any of the plugin guys are going to want to go there with a ten foot pole. Numerous other tools exist to test a drive (including the SMART extended tests)
If you review the Preclear thread, its all about why doesn't the plugin work and why does it cause problems in other parts of unRaid vs why doesn't the drive pass the tests. Personally, I myself don't need the aggravation.