I've made about five or six batches of soap so far - and I've learned that I just don't like the plastic milky way soap molds. I am wondering what the best kind of mold is. I'm looking for a long tub style - 4" width and 12-24" length. What kind (metal, plastic, wood) would be the best, how do you properly insulate it (I have only been pouring single bars before - don't know if the mass of the soap log affects the cooling/curing time) and also - a recommendation of where to aquire it. Any help would be appreciated.