Why would some USB3 enclosures be problematic vs others?

dingobiatch said:

...But for future purposes, I want to do know how I'm supposed to tell if I'll have issues with USB3 disconnects, slow bootup, disconnects, etc. Is it the chipset? Is there a proven chipset I should look for?

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UASP enclosures have usually the ASMedia chips. The ASM1053e supports UASP and SATA-III.

In many cases the cables cause problems. I use only USB-IF certified cables such as:
http://www.startech.com/Cables/USB-3.0/2m-Certified-SuperSpeed-USB-3-A-to-B-Cable-M-M~USB3CAB2M

dingobiatch said:

But for future purposes, I want to do know how I'm supposed to tell if I'll have issues with USB3 disconnects, slow bootup, disconnects, etc. Is it the chipset? Is there a proven chipset I should look for?

Click to expand...

USB3 for drives has proven to be unreliable at the consumer level. Its a more complicated protocol than USB2 and requires smarter chips in the enclosure. Chips run hot and some enclosures haven't done well pulling the heat out. Firmware is more complicated and in the rush to market not thoroughly tested.... especially on Macs. There are a wide variety of firmware settings that the enclosure manufacture can toy with leading to different results even with the same chip set. Its a wild west. The more pro models are better tested but still not without issue. Add a USB3 Hub into the mix and, well, it can get quirky. Seems that most enclosures that support UASP are not ready for prime time.

Since I switched to Thunderbolt my life has been much happier.

I suspect by April 2015, vendors may have USB3 with UASP more sorted out.... but using USB3 with drives will always be an abomination and full of compromise. Perhaps suitable for portable use only.

The host end can also add some issues as USB requires a complex protocol stack, with plenty of opportunity for quirks to show up. Not all Host drivers, let alone enclosures are completely compatible with the USB3 spec. Vendors make money by getting to market quickly and take many shortcuts. Plug it into their old desktop, transfer files, it works... ship it.

Probably some day USB 3 will improve. But now its not ready for prime time. If you are looking for stable I/O, take a pass on USB 3. Today I received my 5th USB 3 enclosure. The first 4 were returned. Spontaneous ejects, improper ejects with sleep, failure to mount, failure to show up in DU, occasional restarts required to mount, etc. Nothing unusual here, its the standard list for USB 3 drive issues.

I think I'm trying them out for fun now as I've already written it off as a serious interface.