I am working on this full Deferred Rendering framework for a long time. Free radical is a realtime rendering engine which i developed with Quest3D. I ended up with some interesting results in terms of performance & Quality.
I made a huge effort to set it up as optimize as possible.
It took me 4 year and yet long way to go. All post process shaders are downsampled, so it runs very fast @ 1080p or higher resolution.
You can download the Beta from the link blow. It's an EXE for all 64 bit windows.
Free Radical have an editor , therefore you can save and load your levels.