scuwp: All windscreens must meet safety standards. Optically if the one they install is not acceptable (all auto glass regardless of brand is not optically perfect) then simply get them to remedy it under their warranty or CGA. IME normal humans won't notice the difference between aftermarket or OEM. Probably come from the same factory!
I don't regard myself as an abnormal human, other than my Aspergers I suppose, but I can clearly see the distortion around the perimeter of the Chinese rubbish installed in my Alphard. It was not there in the Toyota screen. Additionally, the Toyota OEM is a special lightweight unit with additional heat reflection in order to help the interior remain cool so that the a/c has less work to do since the car is a hybrid.
Toyota regarded those aspects of the glass as necessary to the performance as a whole of the car: personally it seems wrong that the AA can legally disregard that in this case and doing so has lost them the insurance of two vehicles at renewal time, as doing so lost Zurich the Toyota's insurance.