Very cool! Yeah I have a wave shaper already and drum type VCO so adding FM synthesis module to my setup would be perfect balance. Probably decide between Akemie castle and IME Hertz Donut MK3. I like the preset options and so forth in the Hertz Donut MK3 and it would match the orange knobs aesthetic of my other 2 IME modules but the coolness of just knobs no screens in the AC module and heritage of Yamaha FM chips is hot.