Motofocus for Refractors?

I have a Televue NP101 and am interested in getting a fine-control focuser for focusing at high powers. I often go to 180x or higher and at that power it is difficult to focus both due to narrow focus range and the shaking when I touch the focuser. I understand there is a device called a Motofocus available for the 101 and was wondering if any refractor owners had this device and how well it works?