My Classé Audio DR-9 amps are over 35 yrs. old and functioning fine. They came with a lifetime warranty. Try to get one of those these days. I expect they were built to last. They are Class AB, so never get as hot as Class A amps, so that also helps with their longevity. I use them in bridged mode, so they provide loads of power and current.
About a year ago I removed the lids to remove dust, and I think I inspected the caps and didn't see anything suspicious.