Just a note, those four SSD's are some very old 64gb ones for testing that I have from digital signage board machines. The plan is to get four 2tb, or 4tb drives when money allows, as with fan modding and looking at potentially adding in extra drives in the back, but for now while I bounce between different candidates and test things, I'm using those. This machine won't be getting used regularly for a while yet unfortunately, but that means plenty of time for testing and getting input from others. Also snapraid does do snapshotting, but it's not continuous like with ZFS, it's in larger incremental chunks.
I have been operating this machine with Unraid for almost three years now without any issues. The only drawback is the pitch noise from the fans. I have been searching for a quieter fan replacement but have not found a suitable option yet.
If you are going to use spinning rust, invest in a large tape backup solution. Other wise invest in a ssd array and invest in a large tape backup solution. Either way you can't rely on this data from a raid array. Even if you do you should invest in a large tape backup solution...or a 2nd array, that is then backed up on a large tape backup solution.
I definitely want to get a tape solution and have a rotating backup in place, I currently have a little SFF machine with a 6tb drive as a target for duplicacy but that only does so much. I have a powervault 822? kicking around but that's only lto2, and it will probably be a while before I can get something more modern. But tape systems are super cool.
