amplifier longevity

Guessing you have not ridden the R1 with the Cross Plain Crank. Like riding a twin with the red line of a IL4.  Selling my Duc to get the R1 and will keep my RSV4R kills the Duc.

My BMW S 1000 RR is killer also. I only do track days and will not ride on the street. 9It's like the new Class D stuff from AGD and Bel Canto.

I am a high speed MOTOGP Bot.

There are Sugden A21's still going strong over 30 years later, so much for the Bogus heat issue.....

Depends where the heat goes. If the chassis is built to isolate other components from the heat, no problem. 

My Sansui 7070 receiver that is ss has been running in my wife's salon for over 25 years never shut off (except power outages). It still works like a champ. This was purchased new in 1978. I think it was the quality of components the used. These old receivers were way over engineered and when said and done were great value. 

The only piece of electronics I ever had fail was a HK receiver. No other amp, SS or tube,