There's not a tree or structure within 100 yards of any of my Austins so I can vouch for their full-sun capabilities. It takes 300' of hose to water them, so you know they don't get watered very often either.
Dark Lady is the only one I have problems with, so I ordered another one from Chamblee. Out of an order of 17 roses, it was the only one I thought was puny. It will have to grow in the 1 gallon pot for a while before it can survive the real world.