I just got a used Bailey 13". The handles that came with it has a "speed control" knob. I understand that just controls how many stitches per minute the machine runs and I have to control the speed at which I move my machine to keep my stitches as consistent as possible. Bailey's offers a Sew Control Regulator with encoders. Does anyone have this? If so what are your thoughts about it? Any problems with mounting it on any specific frames?