Which Readynas

Get the Ultra. The NV+ (and Duo) do not support 3 TB drives. They are limited to 2TB due to the MBR vs. GPT issue outlined here: viewtopic.php?f=24&t=55293&p=313407#p313407

Here's something from another post of mine in reply to the same question:

dbott67 wrote:

...although the Duo/NV+ is a great little unit (I bought one back in 2007), however, it is getting a little long in the tooth. The ReadyNAS developers have recently released an upgrade to the home-user market called the ReadyNAS Ultra in 2, 4 and 6-bay units. These units have a faster CPU and are more suitable for transcoding and media streaming functions going forward. The Duo & NV+ are quite capable at doing what it they were originally designed for (storing/sharing data and streaming media), but it's low-powered CPU is not suitable for doing some of the things that many folks who are into media are looking to do. All ReadyNAS products are based on Debian linux, however, support for the CPU included in the Duo & NV+ (it's a sparc-based CPU, as opposed to Intel Atom x86-based CPU in the newer Ultra series) has been removed in current generations of Debian development. This essentially is going to limit updates to the firmware. Development on the x86 line is much more active, and new features are being added regularly, both by the developers and the community-at-large. So, if it's in your budget, you may want to take a look at the Ultra line-up to offer the best performance and feature set over the lifetime of your purchase. Feel free to ask more questions or let us know some of the things you're looking to use your NAS for and we can help pick the most-suitable model for your needs.