I don't know about 3W and DA, but mine fires each time the magnet passes the Hall switch, doesn't matter if it's 1 rpm or 10,000..there is no delay or advance unless I put a syncro spark module in series with it...A timing light on the spark plug wire shows the prop stationary at any rpm, changing as the throttle is advanced or retarded when the syncro module is connected, not moving at all without the syncro module...The sensor on a 3W uses only 2 of the three wires in the plug, the black and white..A 3W sensor won't trigger mine or C&H's circuit, although TKG says he can make it work...Don't know about the new style 3W sensor, it might be a Hall, the old one definitely is not....