We are always wary of the claims made of certain models. Some suggest that there will be no change in action, but differences can arise after the "break in" period. In some extreme cases, the action can change from lively and easy to roll-over to glacial almost immediately after purchase. There is no known fix for this. It is best to exchange for a different model. Unfortunately, repeated demos will not reveal this characteristic, nor will comparison with models of similar dimension.
It is clear when the equipment begins to wear out. There are measurable increases at the waist and tail. The tips and tails begin to sag. Machine tuning is no longer an option, and hand tuning does not acheive the same results as it did in the past.
There have been reports that freshening up the top sheets and repainting can breathe new life into this worn out gear, but it is best to take it in and have is professionally overhauled.
One can have the firmness in the tips restored, and the size of the tail trimmed. At this age maintenance costs begin to climb and become very high. Once the gear becomes vintage, the costs to ensure a smooth compliant ride become excessive. Even repeated hand tuning, to the point of excess, may not provide a satisfactory glide. Hot waxes should be replaced with liquids.
It is best to avoid completely stripping the bases. Be very careful when using alcohol on vintage equipment.
Caveat emptor.