SkyWatcher Pro 100ED f9 mounted on Meade 12" LX200GPS Unstable unit at best of times - when it was on the wedge it needed 15lbs of weights to balance it. The Meade mount was struggling to cope with it - I bought a SkyWatcher Pro 80mm - it was slightly better - with the shorter focal length (f7.5) it only took 7lbs to counterbalance.