*But there are other options. Yesterday, I was pleased to get a bag of Herculite 2 plaster from Special Plasters, Ltd. This is a very hard-setting plaster used in engineering to create models of metal components, as well as in architecture for decorative features. A large bag of this comes in under £10. A first run tonight (while watching Poirot on TV) saw excellent results. Each component came out crisp and clean, requiring only a little sanding here and there where I put too much mix into the spaces. Even the most difficult parts on the molds - the barred gate, the panelled door and two brackets - came out intact, which they failed to do with the PoP.
Overall I'm very pleased with the way these molds are shaping up. Once I have enough of the right components together I'll run a project to add a small building and walls to the base area of the tower I made some weeks ago.