The nice part of Greyhole is that your redundancy level is determined on a per share basis. Thus, for my Movies share, I have NO redundancy, while for my family photos I can have N redundancy. And for some work documents I can have one extra copy.
Jannie, I have the same setup as zamicro, foto's and really important stuff I have N redundancy, reasonably important documents I have 2 backups and movies and series I have no backups.
I agree with your point on the minimal level of redudancy being very high, but tbh, in the time it takes a raid5 setup with a couple of disks to rebuild I could have reaquired enough movies and series to last me while I rebuild the rest of the library.
Thats why I said at start you have to look at what your needs are. If you want 1 disk failure cover on movies and series then yes RAID is better, however I don't really need that, and the time and space wasted RAID does not justify using it to me. That and I had a bunch of different sized disks lying around. The flexibility of Greyhole is what got me interested.
Another advantage of Greyhole is that the non-disk hardware can vary, and Greyhole can tolerate failures. If my HP server fries its motherboard or the HDD with linux on, I can plug the harddrives into any other pc, install any version of linux and if I install Greyhole with the same mount points specified and shares, the Greyhole array will function after a normal restart without needing a rebuild. Hardware raid will need a similar controller (might be expensive) and I'm not even sure software raid can be recovered in that case.
Horses for courses. I got what I wanted, with each system you build you have to look at what your needs are, and Greyhole fitted mine better than the others. I never meant its better than unRAID or normal RAID, just another alternative that people might consider. Nothing wrong with having more choices
I probably would have tried unRAID as well if I didnt have to pay for it... for now I'm happy with Greyhole, and see no reason to dish out some moola to try it out.