development speed - When creating quick prototypes, is it better to use the language you are going to use in the end?

I have been working with SFML(C++) and Flash(AS3) and usually creating prototypes for some ideas I have.

Is it better to use the language you are going to use in the end (C++ usually) or use something simple and quick (AS3, Python, etc) to get it working and then start from scratch when you start on the main product?

Answer

It heavily depends on what your goals are.

If you're trying to prove gameplay, speed of iteration is probably your most important goal and therefore you should pick a language and environment to suit that.

If you're trying to prove tech (using middleware or otherwise), then your goals would also include choosing what language to use.