Brilliant atmosphere, solid story, well developed characters and excellent game mechanics... what else do you want?
The world is an interesting design which feels part dark ages and part futuristic. Voice acting and dialog are top notch which makes the game very, very immersive. There are also several layers to the world - a complexity that you can either ignore or submerge yourself in depending on your play style.
Stability-wise, I never ran into any issues - at least nothing notable.
If you have not played this, you should. Its old enough now to where its just not that expensive and a really great value. Hopefully this studio will continue to produce quality titles like this one.