Pros
It can be very relaxed. Get your job done and you can count on promotions and raises. The work can be very cutting edge. The managers for the most part let you do you thing and don't get into the mix too much. Unless there is a lay off it is VERY rare for anyone to get fired.
Kontras
Relaxed also doubles for no real movement. They don't change things and when they do it seems to frequently be in the no right direction. I won't say wrong because often the choices seem to just neutral. The promotions are few and far between and seem to be heavily based on who senior management sees most, not necessarily who is doing a good job. You boss also has to like you because it appears they need to burn political capital to get promotions for non-senior management noticed people. Management lets you do your thing, but that means when the poop hits the fan you can get fried too. They don't really know what you do or how involved or difficult it is. Raises are small. Bonuses non-existent. Stock options have been worthless for sometime now. .