Pros
I don't think I ever worked harder in my life before I got to Computer One. It's a full-on workload and there's hardly ever a big period of slack. But the flipside is, you learn a huge amount about the technology they use in their stack and clients' stacks. Definitely makes you grow as an engineer. The team around you expect you to pull your weight and those who don't, or can't, find themselves on the outer.
Cons
Would have liked more downtime and a bit more time for study. Would have liked a bit more social activity. But would I have gone along anyway?