It's hard to compare a Big 4 company with a lot of breadth across the industries with a technology firm focus on a specific area. If you are highly technical, you would gain great depth into a specific niche. However, that many not be useful once you are outside of that niche. On the other hand, at a Big 4 company, you would most likely work on many different projects. You would gain knowledge but probably not enough to become a guru. However, you will have exposure to lots of technologies and have proved your usefulness across multiple areas.