Experience depends on your section, office, and supervisor
Pros
Big company with decent benefits, great resources, and experts from across the country. You get to work on some of the biggest projects in your region, as well as across the country or the world. You are encouraged to join professional organizations and this is 100% paid. You'll be exposed to a variety of interdisciplinary projects in different geographical areas - it usually never gets boring. The company has lots of resources, and will get you the latest software that you need to do your job. Being employee owned was a plus. I took advantage of this and grew my 401k by investing in the company. The company does really well every year.
Cons
Raises were not transparent. Employees with less experience could make more than people with significantly more experience, and there are clear favorites in each office and section. Everyone who is not a favorite may be treated as expendable. The NY/NJ offices are treated like a money making machine. Upper management doesn't treat employees as people. You are given unreasonable utilization goals and pressure to stay utilized. If you need to go to a conference, you either make up all the hours or work extra hours during the week. it is unpaid, even though managers will boast "paid training" for employees. Some project managers have absolutely no technical knowledge and more junior level staff must teach them. There is very little opportunity to grow in the organization. You are treated as a junior engineer for the first 6 years of your career. Even when you get your PE license, you are still a junior engineer. You can ask for opportunities to manage projects, but you won't get them because these just go to upper/middle management's favorite staff. Once you do manage to reach mid-level engineer, the senior project managers and section managers still micromanage your projects. On the section manager side, they typically don't focus on their employees. Mid and senior management is more focused on client development, marketing, and micromanaging your projects for their clients. No one cares about developing staff. If you start out your career here, you will suffer because they'll always see you as a junior engineer. Costs for licensure, any PE review classes, etc. are not paid. The project management software was very slow and inefficient.