Just to Echo the already Fine Advice put out here. This is by my experience only:1st Choice-Masonry Chimney done correctly. Money Out Is Money Out,Make The Expenditure Count...2nd Choice-Best Quality Available Stainless Metal Chimney With Correct Cleanouts As CK Covered. Coming In On A Wing And A Prayer Is The PowerVenter Option. All I Can Say About These Is You Better Stay In An A-1 Hot Priority Maintenance Mindset If You Go With One Of These. If You Want To Be A Light It And Forget It Coal Guy,Then No PowerVenter For You ! Also,never PowerVent a Hand-Fired. Stoker Is What They're For In My Book. Remember,ultimately it's your money. Only you can decide in the end. Do it always as Safely and as with as much Life-Expectancy as possible,and you're a Happy,Warm Guy !