Hiya,
Take a look at Drobo. They have a range of products with eSATA, USB3 and iSCSI conections. We use a Drobo FS 5bay Which has a 1Gb network connection and also the Drobo Elite which has 2 x 1Gb iScsi connections.
I cannot be more happy with them. Our Elite serves as our main network data storage and has 4TB in it at the moment, but if you want a fast expandable NAS to put your backups then the Drobo FS is the way to go.
Let me know if you want more info or prices as we resell them.
Kind regards.
