Richard,
Ross and I specifically talked about running the rotary. I really like Ross' system and I would like to run it. In the past he had a system dedicated to the 2 rotor. It is very much like a 4 cylinder piston system. If he has stopped making it that would be a shame. I don't like the Halltech units I have seen and the alternative is the Motec which is a good system but over priced compared to the SDS.
Bill