You won't find any network storage device that offers more space than the recently reviewed five-bay DS1511+ NAS server from Synology.
This is the first NAS we've reviewed that has up to 15TB of storage space out of the box, by supporting the new 3TB hard drives. On top of that, when used with two DX510 expansion units, the server's storage space can be scaled up to be 45TB. With front-facing drive bays, it's easy to replace or add more hard drives to the systems.
Apart from standard RAID configurations, the DS1511+ also offers Synologoy Hybrid RAID, which is similar to RAID 5, that allows you to add/upgrade hard drives to the system without building the RAID setup from the beginning, hence retaining the existing data. And then after that, if 45TB still isn't not enough, you can use the four USB ports to add more. … Read more