Original product was defective, have received 3 replacements that have also been defective.
D. Bloom, Amazon
24 April 2011
Summary: I purchased ReadyNAS Ultra 6 Plus from Netgear via Amazon.com which was received on June 15th, 2012. I began to immediately experience problems with the device. In the first week of running the NAS device 4 of the 6 installed drives became non-operational. This unit is not sold with drives; however the manufacturer provides a list of compatible drives on their website. The 6 drives installed were all Seagate model ST2000DL003 from that list.
Summary: I highly recommend comparing this NAS to the offering by Synology DS1511+. I returned this unit and purchased the DS1511+, best decision I could have made. The Netgear's interface is nothing to brag about, its more, or less, like a glorified Netgear router. And I've never personally liked Netgear routers (I've had bad luck with them). Your best best is to compare the two following videos: Synology: [...] Netgear: [...
Summary: I have a which has been great but wanted a NAS with more capacity and purchased the ReadyNAS Ultra 6 Plus. From the start I've had a terrible experience it. It refuses to operate with anything more than 2 hard-drives in the system. Netgear tech support are polite but I have been in regular email exchange with them for a month and the problem is no closer to resolution. I would avoid this lemon.