What's the best language for web prototype
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I am in process of deciding on a language to develop a full fledged website. Requirements are following (in order of importance)

1. Rapid prototyping and iterations
2. Fully functional debugging and logging features
3. Highly scalable
4. Clean design (OOD, OOP)

I have background in .Net/Azure and am inclined to go that route. However, I want to hear feedback before going this route. In particular, what are the pros and cons of other platform.

Thanks