I run a Vixen Atlux (the second generation kind with the SkySensor2000-PC - not the starbook toy edition
) on a large home made steel peir. My rig uses Losmandy sidesaddles and O rings to hold a C9.25, side saddle 5" MAK and a Megrez 80 on top of teh C9.25. These scopes are counterbalanced with about 25 Kgs of weight. The mount seems to deal with all this weight very well.
For me the OAG and the more sensitive DSI II mono pro working correctly in light polluted skies were a revelation last night. I really botched up the Photoshop curves processing of the shots above (the real star images stacked where alot tighter - maybe half or 1/3 the size of the stars in this shot - each star got a halo) - but yes at F/10 the stars were beautiful up to 15 minutes at 2.3 metres focal length - that is some pretty good guiding. For the first time ever - ever - the stars after 2-3 hours were in exactly the same position (to the pixel) on my last shot as the first. Even guided - I normal see some drift over the hours - meaning stars bloat. On these shots there was absolutely none - meaning tracking and guiding were as close to perfect as I have ever achieved!