definately the low temp metal alloy is on the expensive side when considering manufacturing. its ok for 1 or 2 pieaces but not for multiple parts.
I found that in spin cast technique though the whole process looks quite easy, it actually has a bit complicated procedure for maintaining the molten alloy temp.
i found this info on weikipedia
A melting furnace is necessary only when spin casting with metal. Understandably the metal must be in a molten state prior to introduction into the mold. However, it is necessary for a spin casting furnace to posses a temperature controller as there is an approximate range that works best for each metal. For example a particular zinc alloy is typically cast between 775-800 °F, whereas it actually melts much lower around 500 °F. If the metal is introduced to the mold at a higher temperature (in this case, above 800 °F), it will start to wear the silicone down prematurely, greatly shortening the mold life. If the metal is introduced at significantly lower temperatures (below 775 °F), its solidification time will similarly be shortened resulting in incomplete or low quality castings. Therefore, spin casting with metal requires not only a furnace with fine temperature control, but knowledge of what range to cast at.
If the rubber mould is distroyed while in production ..its gonna create problems to fulfill the orders on time. All depends on the furnace with temp control.
anyone herd of white metal here?...i have seen lot of intricate designs made in it.i am attaching a pic of figures made in white metal.