I then simply connected the MIDI device up to the Strymon Timeline and went into the MIDI settings in the Strymon Library software and unlike the other device, this Roland UM-ONE tested perfect and immediately I was able to retrieve, rearrange, re-name all my presets as well as update the firmware on my Timeline

Works flawless with my iPad Air & my old Roland A-33.

device should have worked painlessly, but Roland has not yet updated drivers to work with Mac OS 10.10 at all

It works flawlessly with my Roland AX-1!

So I ponied up for the more expensive Roland for my Roland synth and it worked perfectly.

The Roland UM-ONE had no problem connecting my midi device to my computer and everything worked as advertised.

Looks like Roland released the 10.8 driver on 2012-07-26, but as of this writing, it hasn't been updated for Apple's latest incremental update (10.8.2)

What sold me on this one was the positive reviews, the lack of indication from negative reviews that it wouldn't work for me, and Roland's reputation.

Unfortunately, Roland doesn't make it easy at all to find it on their website's product page either