Pros
Google has plenty of talented engineers, impressive computational infrastructure and resources, and the culture to build products that make big impacts. Working for Google is an ideal start point of young engineers or new graduates. There are plenty of challenging problems to solve, and you have the flexibility to choose the projects that interest you most. I am not saying that you can give up the current project at any time. it is responsible to finish the projects that started, but you are encouraged to switch projects every 1 to 2 years, or at least, you can do the "fun" things with your 20% time.
Cons
If you want to be prompted sooner than the majority, and you are not lucky enough that work in a highly visible project, then you have to pay much more than usual to beat the performance of others - because others are good too.
