This seems like a great price for a budget NAS prepopulated with 4TB (2 WD Red drives).
Looking at staticice this is definitely better than half price of anywhere at the moment:
Staticice search for model
2 years warranty
In February, WD released firmware with an OS update (and this model is supported) with up to date security and additional features.
This page has a comprehensive list of features (2nd column from right in the table): https://support-en.wd.com/app/answers/detail/a_id/29389
Some things that stood out for me about this model are that it can run Plex / DLNA server plus claims it can do transcoding (I don't know how well).
A word of warning though - it only supports SMB2 and SMB3. Because it does not support SMB1 (this is deprecated and insecure) it means that some old devices (media players, TV's etc) that still use SMB1 will not work with it. [So if this is important to you, if you buy this, don't upgrade to OS5, and you should be ok - except the old OS3 will not be supported by WD if you need support]
Mwave are currently offering fixed price $5.99 delivery on all orders.
Note that if paying with Paypal / Credit Cards, it will incur additional 1% ($2.48).
Don’t even dream of running Plex on this. I have the 8tb version of this. Not only performance but you are locked into an old version of Plex through the WD app ecosystem. Used to be easy to side load newer versions but OS5 upgrade has closed that off. Get an Nvidia shield pro paired with NAS like this is a better option or a better more modern NAS. I must have got this EX2 4-5 years ago now