Hi Garry,

if you are referring to the Unimould system then the answer on a 120 degree cure would be yes and no! The design temperature is 80°C, at 80°C the service life of the tool will be almost indefinite, however we have on occasion pushed the tooling to °C with good results (but never higher), as you are well beyond where it is intended to be used I would be prepared to expect the moulds to degrade more quickly and potentially lose some dimensional accuracy. I very steady ramp up to the 120°C (say 10°C/hour) to post cure the mould before use would be essential to prevent the mould from off-gassing and softening whilst in contact with the prepreg.

You are in experimental and out-of-parameter territory sotry this at your own risk!  My advice would be to stick to the 8hr @ 80°C. You will probably find that with most ovens this will actually use less energy than 2hrs @ 120°C