These drives went on sale so I decided to pick up one to expand my home lab storage capacity. After doing some research on the Red vs Black edition, I found a few posts that referenced head parking issues in the 4TB Red series that significantly reduce the drive’s lifespan.

http://www.reddit.com/r/DataHoarder/comments/1wcpl7/4tb_hard_drive_wd_black_or_red/
http://forum.wegotserved.com/index.php/topic/29078-wd-4-tb-red-are-apparently-having-head-park-issues/
http://forum.qnap.com/viewtopic.php?f=182&t=83577

Apparently you can run a utility against the drive to correct the issue with idle3 http://idle3-tools.sourceforge.net/

Before setting the idle timer to 0, I was getting 273 Head Parks/day. After the utility was run, I am now showing 0.67 Parks/day.