Just an update . 3 years ago picked up a 2011 lopi insert . After a lot of reading on the forum here , I installed it with the duraliner system . The Lopi has exceeded all my expectations . It mostly gets used when the temps are 20 and below like today in western Pa. My add-on furnace carries the major heat load . Burning 3 year css oak in the insert , easily burns 8 hrs on a full load . Thanks to everyone here for the advice on purchasing this . It’s a great investment and addition to our home .