Here is my situation:

I have some digital data for which I need high redundancy but not necessarily high availability so I am trying to cover both the scenario of disk failure and that of NAS failure.

I was thinking of purchasing a two-bay NAS which uses the EXT3 filesystem, and setting up a (software) RAID 1 volume on it, and using an eSATA connected drive as a backup (also using EXT3).

I know that a RAID 1 volume will continue to operate with one disk failure until replacement of the failed disk and rebuild of the array, thus covering the scenario of hard disk failure, but what about a hardware failure of the NAS itself? Would it be possible to remove either one of the disks from the NAS and connect it to a Linux PC and access the data since the disks are simply a mirror of each other with no parity data?

For a NAS using software RAID 1 and EXT3, what would be the likelihood of data corruption assuming NAS hardware failure?

Are there any better alternatives such as a multi-bay NAS using RAID 5 or 6? I assume that once the RAID level includes parity data, it would not be possible to simply pull out one of the disks and read it in a PC.