Pros
-Got me started in my career as an auditor
-thorough tax law training
-many senior auditors helping you learn the profession
Cons
-communication from management is not always transparent
-when you are at the bottom of the ladder, you get verbal abuse from not only POA and taxpayers (understandable, given this is the IRS), but also management/OJI's. They want to look good to their bosses and will throw you under the bus if they have to in order to save themselves. Even if they gave you instructions that got you in trouble. They SHOULD be supporting you in your function as an auditor, but they'll do whatever is easiest for themselves ultimately.
-on job training can be disorganized
-bureaucratic culture
-like many other companies, a lot of things you're expected to learn by yourself. Such as how to avoid POA delays.