Test a compiled Symfony2 Container as that is what SF2 normally uses in production.

Symfony normally only compiles the container once when the cache is regenerated.

The $rawContainer is normally dumped to disk and then required later.
This is why the Container class you've been using is called ContainerBuilder; because you use it to build a Container and then write it to disk.

On my machine I went from 0.2 sec to 0.02 sec on the tests.