Vantaggi
You are never left wanting for work. And although a large part of it can be grinding at times, individually you tend to learn different aspects. Personally, I have picked up a more general knowledge about chip design process that I wasn't as exposed to previously. The company is never standing still - there are new product ideas and engineers are expected to handle the challenges of new technology, meet market deadlines and do it with a fairly functional chip. If you can do that and as management grows to appreciate your work, you will be properly rewarded (although I was initially disappointed). Generally interactions between engineers and first-level management are not political, but based on performance and there is a healthy respect. Communication is valued and hiring reflects the importance of being able to work with other team members.
Svantaggi
As with any big companies, there are politics and one can easily get lost in the shuffle. There can be vast divergence based on the manager's rating and what he values which can be unfair. And some groups have managers who are more vocal about their teams. Also, some divisions can be rated more important to the company and there is more growth there ...