Pros
They have above average pay for position and offer a good number of financial benefits and attempt to take care of their employees during busy season by offering delivered meals, allowing expended meals, etc. You won't get exposed to any greater level of businesses than at a big 4 firm. You'll learn a lot in a short amount of time and is a great resume builder. Great PTO benefit.
Cons
Hours. Sometimes it is difficult to draw a line between busy season and off season. Truly it is just all a busy season and January through March/April is your peak time. If you have a family, it is very difficult to manage both your professional and personal responsibilities. I left after a fairly short period of time with the firm because of this reason, I was often forced to choose between work and family. Often times, you will work close to midnight or later on a consistent basis to meet deadlines which definitely negatively effects your mental and physical health.