I play with old paper all the time. Ask those who get psotcard exchange images from me if you think this an idle boast.
When you test, don't pull from the top of the pile with old papers before deciding the paper is crap.
There seems to be some kind of interaction with the packaging that makes the top sheet of old paper often behave differently from that found further in.
Old papers loose contrast in my experience. A step wedge printing test can be very helpful in calibrating how they currently react.