The AZ3 mount...
Seems like a good idea, but oh my goodness, what a horrible bit of gear when you actually start using it
Puts the scope in a very precarious unbalanced position when pointing towards zenith, at terrible risk of toppling back on itself! Happened to me one time and thankfully was able to catch the scope, with my face!! Can't reach zenith anyways! Can overcome most of the unbalanced issue with a bit of DIY and still can't reach zenith, and for the DIY effort involved best to chuck the AZ3 and buy a better az mount.
Alex.