i just wrapped my down pipe today. 50 feet for 40 bucks at summit. it will help a lot, its worth it from what ive heard. If you do it grab the high temp silicone coating, to spray over it to keep the water out of it. ps dont wear anything white while doing this.
There's a local place that does ceramic coating and is very reasonable. Ceramic does a better job of heat retention than the wrap. Matt
i did the up pipe and down pipe with 50 feet, with about a quarter of it left over for other projects