s/schneller/besser

Speed: thanks to its Just-in-Time compiler, Python programs often run faster on PyPy. (What is a JIT compiler?)
Memory usage: large, memory-hungry Python programs might end up taking less space than they do in CPython.
Compatibility: PyPy is highly compatible with existing python code. It supports ctypes and can run popular python libraries like twisted and django.
Sandboxing: PyPy provides the ability to run untrusted code in a fully secure way.
Stackless: PyPy comes by default with support for stackless mode, providing micro-threads for massive concurrency.
As well as other features.