I'm surprised to see people recommending HiH for heat.
Above and beyond the cost and hassle to install, I can't imagine risking a HiH leak considering the widespread availability of heated fuel pickups, FPHEs and Vegtherms.
A good debate on HiH:
http://biodiesel.infopop.cc/eve/forums/a/tpc/f/159605551/m/3961053671?r=3961053671#3961053671