Two years ago, I was asked to test the optics of an AstroScan. There was no requirement, just curious to see how good it was.
I took the scope apart to test the flatness of the window (how good would it be in transmission) and is the primary mirror
polished to a asphere ( at least -1cc)
So the results were: the window was a few fringes flat, convex one side and concave on the other. The total gives zero power
and a fine transmission. (the black dot is my reference dot) The primary was tested with 75 line screen, it did have an aspheric shape
(I did not do a KE test) The secondary was 1/8 wave, the fringes were hard to image and not shown.
Over all the scope was better than expected and performed wonderfully, a very nice scope, even at high power.
I make no judgement of the rest of the scopes out there, but this was good to see as just one data point.
Attached are images of the testing. The window was tested with a 1/10 flat, under a sodium light box (Shop model) and the
primary was just a simple R screen setup. I think this scope was made very well. My niece was very happy to receive it.