I had a GSO low profile 10:1 focuser on my 16". The focuser mounts so
that it is horizontal to the ground. Even then I found it struggled as most
of my ep's are 350gm+. When I brought a 31mm T5 it became almost
useless with too much slop that I couldn't remove. The fine tuner was
non-existant, and the rough focus would more or less grind and jerk
under the weight. So I ditched it and upgraded. Was looking at Moonlite
but then along came a deal on a Feathertouch. Haven't looked back
GSO focusers do ok, until you start using heavy ep's. No matter how I
tried to adjust it it just wasn't up to the job.
Cheers,CS