OK, finally got the unit to function properly on my 40. After multiple calls to Vintage Air by the shop who installed, the fix was to switch two wires on the AC micro-switch. So it is finally working. One comment on the "defrost" function is that the amount of air that is actually directed to the defrost vents is weak at best.
I'll run this system as long as it'll last but if I ever need to do anything different - I'll find an alternative.
As for my sons 55, he recently had to replace the fan on the unit. When he took the original fan out, it was missing well over 20 of the 50+ blades. He found them in the bottom of the unit blocking the air outflow. He though he got them all out but after installing the new fan - he can't get any air flow out of the unit now. He'll most likely wait to have an opportunity to get it back to the original shop now to see if they can get it working. This unit for his 55 has cost a boatload and I would definitely suggest to NEVER install a Vintage Air unit in a 55. Don't make our mistake - find an alternative if you can.
Sharp38 - thanks again for the contact info. I ended up not calling as the shop I used was in process of trying to work with them to get an answer. I'll most likely hold off until they can get to the 55 and see how that goes.
So after all of this I'm still of the opinion as I initially said, "Vintage Air - Buyer Beware".