I wouldn’t recommend buying a WDTV Play ( no MPEG-2 no Network Shares no Themes support etc…)
*it’s basically a stripped down cheaper media player missing features the other WDTV Devices have*
Feature Comparison here: http://www.wdc.com/en/products/homeentertainment/mediaplayers/
I would recommend buying a WDTV Live Streaming (SMP) instead …
(or a Live Hub, but if you need the convenience of built in Wi-Fi then the SMP is the go.)
4TB support ? i can’t say from personal experience, but some people have reported it works OK
http://community.wd.com/t5/WD-TV-Live-Streaming/4TB-HDD-on-WD-TV-Live-GEN-3/td-p/595497
