James50, I don't see it as "obvious that Mac does not have the same confidence....". Mac sells many more types and volumes of products all over the world. It may just be an accounting nightmare to have to go back into their records for 20 yrs. Mac amps and preamps have long been known to last 20 to 30 yrs. One might also deduce, by your logic, that Bryston feels they need to offer more to compete. At the end of the day it doesn't really matter what you or I or anyone for that matter "think" what the reason is for different warranties. If it was hurting Mac, I'm sure we would see longer warranties from them. FWIW, I own Maggie 3.6's, and the Bryston 500 would be at the top of my list to demo if needed. Right now I'm happy with my MC1000's. Good listening.