What is the lifespan of a good SS Amp

Consider to go for a used SS Amp.
Around 4-5 years old.
Wonder how long one good SS Amp lasts.
I know that some 20 yo tube amps cost more than their
original retail price and they may last for centuries
(just need tube change)
but wonder how it is with the SS.
If I go for 4-5 yo SS Amp will I be able to enjoy it for a long years or after another few years it will start giving me problems.

Thanks for your help.