Going to need a taller chiller in the new system. Going to get one form NY Brew Supply(same place I got my last one, nice piece just not tall enough for my new Digiboil). Noticed that copper and stainless are roughly the same price. I know that copper SHOULD cool faster(all things being equal) and stainless should be easier to maintain. Price is within $2.... What are the major pro's con's of each hands on?