Pros: Very nice construction, easy to setup, the ability to house both 2.5 and 3.5 disks is pretty fantastic. Read/Write speeds are adequate. Linux sees each drive independently, correctly mapping to /dev/sdX and /dev/sdY respectively, however...

Cons: ...I don't know if it's an issue with the jmicron chipset or what, but the drives fall out after only a few minutes of idle, which is not necessarily a huge issue, but is pretty annoying when backing up some snapshots and stepping away for a few minutes. What worries me though, is the drive fallout occasionally happens during both reads and writes. I've seen it happen multiple times, but have not been able to replicate it with any series of steps, so... dunno.

SMART tools completely chokes on the enclosure. It can see each drive independently with the jmicron flag, but is very flaky. If it decides to freeze up the enclosure, it certainly will, without warning.

Other Thoughts: Now that btrfs has reached a point where I feel very comfortable trusting it with all of my data, I bought this enclosure as an entry point for long term archiving. The idea was to start with a couple 1TB HGST 2.5 drives I had lying around, build a btrfs mirror (on top of LUKS containers,) then eventually scale upward with 3.5 NAS drives and eventually graduate to a bigger enclosure, allowing conversion to a btrfs RAID10 storage solution.

I feel this is a fair solution for long term archiving on tight budgets...

I'm fairly confident the issues I'm seeing aren't with the drives. Both are fairly young drives, and have been tuned to behave more like NAS drives. I've been unable to find a firmware update for the enclosure, if one even exists...

If anyone has any more experience (and wisdom) on these jmicron USB enclosures, I would greatly appreciate any advice.

I'm just a little disappointed is all. I LOVE TrippLite ISOBARs and was hoping their JBOD enclosure would be equally as good. It feels like they added this to their product line just to fill the niche, but they really haven't put much effort into making this a grade A product. If you're reading this TrippLite, I am more than eager to bump this review up. Otherwise, I think I am going to see if NewEgg will allow me to swap it for something else.

Manufacturer Response:

We apologize for the experience you have had with the U357-002. We will need more information to determine what is causing the issue. Please reach out to our Chicago-based Tech Support Team at 773-869-1234 (M-F 7AM-6PM Central) so we can assist you.