Was wondering what PMA-5 users would recommend for a portable keyboard controller for the unit. I've been considering some of the older Yamaha portables (PSS-480, etc.), some Casio MIDI portables and possibly the Roland pc200mkII. Don't need anything fancy (smaller keys are fine, prefer 49 or less), just want to input data using actual keys instead of the PMA-5 itself. I'd really like to find one of those older Novation portable controllers they quit making a few years ago. Any recommendations would be appreciated.