I'm new to this group but not new to wood stoves. We have owned our Buck Stove 91 for over 10 years and purchased it used...so it is at least 15 years old. We use our stove all the time here in Ohio, probably three months of the year full time. The stove has never been running the way I've heard it should so I we put a stainless steel liner in and always check the moisture of the wood (between 7-14%). The glass on the stove would get very dirty with black shiny creosote. Also, every year I have removed the Catalytic Converter (CC) and cleaned it...no real damage...looked good to me. I talked to the local fire place shop that sells Buck and they said the CC doesn't go bad...if it isn't broken, cracked, or clogged don't worry about it. Anyway, this year the glass got very bad, very fast. I decided to purchase a new CC, and it cost $300..ouch! Anyway, it transformed the stove I can not believe the difference it made, it generates so much more heat and the glass stays way cleaner, just a little bit of a smudge on the corners after a week of burning. Anyway, I just wanted to pass this tip along hopping it might help somebody. Thanks.