Durability of Mark Levinson 20.6

I've recently purchased ML 20.6 monoblocks from 1993, which has never been serviced. It is in perfect condition and in estimation of the seller has 10000 hours of operation. It still works perfectly. I wonder if I should replace any caps and other components after 15 years of operation?

Caps at 20 years if it is still doing well.
(Why fix something that isn't broken!)
Agree with Elizabeth, but if it were me I would remove the top and/or bottom cover and at least do a visual. If there is anything leaking from a cap, then I would consider replacing; if all looks well, I would give the interior a gentle blast of air to remove dust and not worry about the caps for several years. Indeed, ML amps are quite durable.
Wojtek, I enjoyed my ML 20.5s for 16 years. Babied them and never had any issues with them, just great music always. Checked inside before I sold them and there was no sign of leakage of any of the caps. Last I heard from my buyer, he was still enjoying them with no problems.