Great diagnostic tool (Hardware & Software)
So, since I've gotten tired of fighting with Linux bootloaders and attempting to code menu systems for general USB booting, I did a lot of research and found these gems a few years ago.
What I wanted was to be able to boot an ISO (any variety that I may have for OS installation, utilities, games, unRaid, etc)
ability to use it as removable storage to hold extra utilities and drivers and/or games.
And for the file transfers to be fast (so USB 3.0+)
What I came across was a product by Zalman
the ZM-VE300
It can mount a virtual CD-ROM/DVD (and even a Blu-Ray Image)
http://www.zalman.com/eng/product/Product_Read.php?Idx=674
There is a newer version the ZM-350 but I'm unsure of what changes there are. Firmware is upgradable/updatable.. Can also mount virtual volumes. like VDMK, etc.
I've tested it with a Blu-Ray image as large as 55GB (I forget the movie) but ran perfectly as if I had my disc in the drive.
Some older systems either won't boot with it plugged in or recognize both the HDD/Virtual CD-ROM, so you have to set the unit to one or the other and save the settings and then even older system (like single core older Athlons/Pentium 1/2/3 systems).
If the device is operating in usb 2.0 or less, the access/activity light is white. USB 3.0 the light is blue..
Best part? It's cheap. ($30-$50 USD) and seems to deliver full USB 3.0 speeds (tested with my Corsair Force GT drives)
I enjoy mine.. I might pick up a couple more and one of the ones that has security built-in with the passcode. Look up on their website and go to Storages and External Enclosures.
Anyways, I don't post much, and I'm trying to contribute and help others out. This device is pretty versatile. My only complaint is that I wish that it had more of an industrial design.
Side note, if you lose your USB3.0 cable, a Micro-USB cable will fit but you'll be limited to USB 2.0 speeds I already tested it on mine. Some of the devices I own that are USB 3.0 and have the micro connector won't work if you use just a micro USB cable, you actually have to use the full micro 3.0... so this is a plus..
Enjoy!