Pros
Being involved with leading edge technologies. It was always fun to work with things that "didn't exist yet".
Cons
The constant instability; when things are going well you can always assume it will turn around. There was not much consistency in the overall roadmap and changes came late in projects. Also, the marketing names did not match up with the internal codenames which did not match the silicon designers' names so you had to know 3 sets of names depending on the audience. That got frustrating after awhile. Also, the culture of secret management was a turn-off. There was a lot of information that could not be disseminated down to the engineers, who often ended up doing work that the could have avoided with some information that was available but not passed on.