Can anyone recommend a good NAS for use in a home-server environment? I would request at least 2, preferably 4 disks, and I am most interested in good to excellent throughput for file-server and backup purposes - don't need any of the fancy media-streaming or -sharing features, that's not of interest to me.

For a 4 or more disk solution, support for the various RAID levels (0, 1, 1+0, 5) would be a plus - especially if supported in hardware (rather than just a software emulation).

I just need a place to put my collection of data, ISO images, and so forth - and since several external disks (self-built and off-the-shelf) have failed so far, I'm looking into a more reliable solution.

Marc