Old SS amps

What are people's experiences with old SS amps. And I'm talking old like close to 20 years. I guess this can be called vintage(though to me it's yesterday.)

Either you bought it new and have had it that long or you bought it used.

Is buying it used a really bad idea even though it was owned by one person with no service issues? Like an old Pass.

I hear something about capacitators needing to be replaced. Should it be avoided like the plague? Am very interested in one but don't want to be stuck with a cat in a sack.

Thanks for any thoughts.