It is possible to have a great experience with this company or a not so great one- it depends a lot on your supervisor, what office you are in, and how your own skills and inclinations connect with them. Especially if you are unattached and willing to travel, it can be a wonderful place to work and many of your coworkers will be very good people. However, if you want to remain around home and desire a stable schedule, especially if your job involves fieldwork you may have difficulty keeping a steady stream of billable work coming across your desk. Like many consulting jobs, your ability to survive in the long term is determined by your ability to find and keep billable work. You will need to market yourself, within and/or outside of the company, depending on your career level.
Pros
Good pay and benefits, many good coworkers
Cons
Constant pressure to remain billable, layoffs not uncommon