Very nice review Greg! AP makes great stuff. Even their older stuff is quite nice.
I am using an older AP900 with my TEC ADL300 and other scopes. The whole system weighs nearly 30kg which is almost at the limit of the mount capacity.
Despite this, I recently got 0.47 arc secs RMS total with phD2 on a night of excellent seeing. The FWHM for my entire luminance stack was 1.8 arc secs with the ADL.