Okay so I purchased the unit and am waiting for it to come in. I still need to make the call on the stack. Bought a Quad 7100, which allows for the air-cooled or the Duraplus insulated pipe. The pricing is drastically different between the two; like $1,000 vs $2,000. Of course this is 8" pipe which is ridiculously expensive. I have always gathered that insulated pipe is better and recommended for colder climates, which I am on the border beings I am in NW Illinois. Also, the air-cooled pipe requires an air-cooled kit (which comes with the unit). Not found of that idea. Should I just swallow hard and get the packed pipe?