Big vintage amps worth paying for and keeping for a long time


Lamm hybrids, Rowland 8t, Levinson 23.5 etc. How reliable are they and how expensive to fix if something goes wrong ? Capacitors, resistors needing replacement, after 25 years, 30 years, something else ?
I didn't mention Gryphon and Nagra, as examples, they are too expensive even old.
inna
Roberjerman, do you mean a Perreaux 2150B? I too have one, sitting in my garage. Thanks for reminding me🤔  
@tubegroover : my mistake! I have the 2150B. Big and heavy! 200 watts/ohms, 400/4ohms. Clipping at 300+ and 500+ watts respectively! Sound quality as good as Levinson or any of today's expensive amps! List price $1500 in 1983. I bought it to use with my restored DQ-10's. A forgotten "sleeper" amp! I'm holding onto mine! I suggest you take it out of the garage, clean it up and put it to use! Or sell it to someone who will appreciate it!