I bought one recently for my WO Megrez 80. I find it great. I think you could mount it on a Skywatcher newtonian, if you are handy with a hacksaw and trill... and can get a little sleve made up to adapt between the diameter of the skywatcher's focus knob shaft and the accufocus coupler diameter.
See my thoughts on it here (with pictures of how I adapted it to my Megrez)...
http://www.rogergroom.com/rogergroom...m.jsp?Item=424
Roger.