I would also add that a largish company isn't one place, it is many smaller places that only looks the same from outside.

Once you're past that 150 number or so, you will have multiple cultures and environments. There will be the small hot next thing, the big incumbent, the team everyone is waiting on, the hasbeens, the guys in the corner no one knows what they're doing, the guys everyone has to work with even though no one knows why, etc. Some traits will be the same, but environment varies a lot.

See recent discussions on Amazon for instance. Some people disagree completely on their experience.