Pete, call me old fashioned...I still focus with the 5 nose-picking digits I inherited at conception and a high-quality Bahtinov. Furthermore, I am one of these nuts who sits out next to the scope all night, refocusing every 30 minutes, and generally enjoying being outside looking up (have a visual setup concurrent to the imaging). I even have gone so far as to remove any auto-focusers from scopes I have bought. Eh, it's just what I like - all part of the fun IMHO, and automatic anything to me is droll.
I have had several SharpSky Pro units, and only ever fitted one. I recommend them highly. No issue with slip etc. I have been considering purchasing another for my FSQ-85 but so far have refrained.
I have heard good things about these:
http://www.optecinc.com/astronomy/ca...lynx/19765.htm