It's based on the Axiom Pro but I have removed the irrelevant info, and added patch up/down (this appears to work only for plug-ins that have presets defined in Studio One but no through their own presets), and also added the Inst button which shows or hides the instrument on an instrument track.
Once I decipher how the active components work in the device model I hope to make it as comprehensive as the DirectLink driver I wrote for Reaper.
Studio One v2.6.1 Professional
Mac Mini i5 (2012), OS X 10.9
Akai EIE Pro / M Audio Axiom mkII / Emu XMIDI 2x2 / You Rock Guitar