HGST DeskStar NAS 3.5" 4TB 7200 RPM 128MB Cache SATA 6.0Gb/s High-Performance Hard Drive for Desktop NAS Systems Retail Packaging for $129.99
Newegg has the 4TB HGST NAS drives on sale for $139.99 - $10 coupon code EMCRHRH26 = $129.99. This matches previous popular deals and is the lowest I've seen these drives at. Way better than WD or Seagate. Cheers!