C# is faster than Python, no question, however how much time do you really spend in your Python code? I don't think I've ever written a view that took more than a few ms to execute, with database queries being the slowest part by far.

If you're executing jobs that calculate things or other batch processes, you can compile them to C/C++ pretty trivially and have a 50x speedup, depending on your loads. Plus, PyPy is getting really, really good.

However, I am as biased as it gets, so take this with a grain of salt.