So after about 2 months burning 2 year old C/S/S Ash & Silver Maple, this is the amount of creosote that I was able to sweep out of my liner. I swept from the top down using a 6" Rutland Poly Brush. Due to the bend right around my block off plate, I was unable to get within a foot of where my liner connects to unit. I'm considering a Sooteater from the bottom up to tackle that issue. The creosote amount was very minimal, less than a cup.