Hi Joful- FYI, 2-5 years for Jotul cats was from Jotul seminar training (worst case scenarios typically) attended years ago- I found that most people never replaced their cats or if they did, they would last typically 7-10 seasons. Corning (Condar cc maker, who Jotul used), their present warranty is up to 5 years, 1st year 100%, 2nd 60%, 3rd 50%, 4th 25%, 5th 10% that they will cover. I think you're right, most folks will burn it with no cat and bypass closed, after the cat crumbles or plugs up. I have a friend with a 12, they won't give it up, but never run it in cat mode. It goes into a 20 foot class a chimney, runs very nicely too, I have to say. Just having the bypass closed and no cat I guess slows down the air flow enough to keep it controllable. Anyway, have a good one....