I have never had a Ketar, but played accordion many moons ago. This thread led me to thinking again about a light.simple setup for small venues. I could use it with my SD40 with harmonica and vocals, or, even solo. I am looking at the new Alesis Vortex 2 @ $299.

https://www.youtube.com/watch?v=6LtxoQBuacs

I know Uncle Dave has one, and would like anyone's opinion. It is wireless with a proprietary dongle(USB) and standard midi. I don't know enough about wireless to know if it would work with the SD40, but would with a laptop.