I've been to the Foundry last night for the first time. Man - this is huge.
While I was exploring, it was the first time I got aware of the ambiance sound. This means in the other areas it works very well for me, staying in the background matching/enhancing the game experience.
But when I saw all the industrial environment I suddenly relialized the actual ambience sound does not match this at all. Some metallic bangs, something more "industral" would be a better match imho.