I think your concerns shouldn't be concerns. I have been in this Highend Game for well over twenty years, like Lugnut have never had any failures in that time based on the electronics. I have had switches break due to my carelessness (Theta DAC, very fragile dip switches) comes to mind.
A friend of mine has a Krell KSA100 power amp made in the mid to late 80's, this amp runs so hot Krell even elected to put two fans in them, he uses it daily. This amp has never had any failure or a service. I have told him he should at least replace the fans just for procautionary messures, but he hasn't even done that.
Tube amp equipment is a little different, periodically one does have to have the tubes changed and the amp at that time will need to be re-biased, depending on the amp you would consider, even that can be done by the owner (you). Most tube amp owners (me) like to check the bias more often just because...... Tube preamps, just a tube change every 2-4 years and off you go. Un-like the mass merchandized electronics high-end equipment is not a throw away. Have fun.........Bob
A friend of mine has a Krell KSA100 power amp made in the mid to late 80's, this amp runs so hot Krell even elected to put two fans in them, he uses it daily. This amp has never had any failure or a service. I have told him he should at least replace the fans just for procautionary messures, but he hasn't even done that.
Tube amp equipment is a little different, periodically one does have to have the tubes changed and the amp at that time will need to be re-biased, depending on the amp you would consider, even that can be done by the owner (you). Most tube amp owners (me) like to check the bias more often just because...... Tube preamps, just a tube change every 2-4 years and off you go. Un-like the mass merchandized electronics high-end equipment is not a throw away. Have fun.........Bob