Joe...it depends. Most people don't leave their tube pres or amps on 24/7. So if you estimate 3 hrs of usage a day (which is a lot), then you will use 1095 hrs in a year (assuming you listen 3 hrs a day every day), which for the 5000 hr tube life mark gives you 4.5 yrs of usage, and at the 10,000 hr tube life mark, gives you 9.1 years of usage. And that is with very aggressive listening assumptions. Not too bad really. You will probably change the amps due to the LuFlu before running out of tube life
