Hi Stewart,
I used to own a Meade SCT (10" LX200), and I found the focuser knob created quite a bit of image shift. To remedy this, I went the route of a crayford focuser (in my case I got a Williams Optics 2 inch model -
http://www.williamoptics.com/accesso...d_features.php ).
In short, it was a fantastic improvement. I loved it. The only complication in a fork mount design is that it can bump into the base of the fork - and may therefore restrict some observing around zenith.