Parasound JC-1 - How old is too old?

I feel that age is particularly important with Class A designs. All those components have been living in heat their whole lives.....

I checked with McIntosh before I bought my used components and was told 20 years, unless they are bulging or leaking, then immediately.  Not sure for other brands.

Yes, that is part of my concern, particularly if the amps were used inside a cabinet which did not provide adequate ventilation. No way to know on a used amp. 

I owned a Krell FPB-300 (which also ran warm) that I had recapped when it was about 10 years old (only because it was in for service for a broken speaker connector) and it started giving me problems after another 10 years. The cost of repair at that point was prohibitive so I traded it in to a dealer that wanted it for parts. According to a dealer I talked with, failing caps was not uncommon with this series of amp.

Since the JC-1 has been around for 16 years now, I'm worried that an older pair is probably close to being in need of repair even if it was treated well its whole life.

But I'd like to hear from folks that own older units to understand what their experience has been.