Hi, Scott. I use a ReadyNAS here as well (see my review in
my blog), and it is much better than before.
There's no way, however, to write directly to the device. You have to use images. Even with AFP, there's just no way to properly save your ownership, groups and permissions. The alternative is to move to a proprietary file format, which I just don't think is wise.
It's pretty rare -- very -- to have a bad sector happen on an X-RAID configured device that would impact data. And that bad sector could just as easily happen in the drive's header/directory...