Does the pypy3 JIT compiler improve fontmake-based compile times?

[PyPy](https://www.pypy.org/) is a Just-in-Time (JIT) Python compiler that can decrease execution times in some long running program scenarios (those that exceed the multiple second level warm up time required by the JIT compiler). It is highly compatible with Python code and has been used with the fontmake compiler Python pipeline sources.

pypy3 is the Python 3 support branch of pypy.

[pypy features](https://www.pypy.org/features.html)

Does it improve font compile times? If so, what type of font project benefits and are there downsides / workarounds required to use the approach?