Pros
You will work with very skilled and talented people on great clients. Thus, it is a great place to learn and to develop as a professional. Flexibility is available for those who are "on top of their game". High performance is rewarded. New tax staff are encouraged to rotate through various groups and are required to get diverse training. This provides a broad skill set to build upon. You will attend a national training for a week every year and local trainings and online training is always available if you have the time. The San Jose office is very oriented toward technology clients and venture capital clients.
Cons
Just the normal stuff you would expect working at a large client service organization -- resource managment issues and quite a bit of admin. Lots of hours at times. Clearly working for a big four accounting firm is nothing like working for the government. If you are looking for a eight to five job then most of the time this isn't it. Overtime is part of the deal but doesn't have to occur while you are at your desk. Beyond office hours no one really cares if you are at your desk or not. If you get your work done right and on schedule it will show up in your reviews and you'll be rewarded for it.