I just came across the in-flight mixture control offered by Bob Violett Models. This is apparently intended for ducted fan installations, but I see where one is installed on a Moki in an IMAC model as a convenience for needle setting without having to cut another hole in the cowl. I have an Aviastar 1.50 with a sensitive needle, and I notice a very significant change in mixture between full tank and low tank--enough so that I've had trouble finding a setting that will give me good performance through a ten-minute flight. Has anyone used this device for managing temperamental engines?