Pros
There are great opportunities to consult for a variety of industries across the globe, while working with a truly interdisciplinary group of professionals who like what they do. Technical skills in the company are top-notch, and most mid-level managers care about their colleagues and subordinates and try to help everyone advance. Time off is very flexible, and the company does still retain some of the entrepreneurial spirit that it once had--if you can identify, market, and win work, you will be recognized, rewarded, and sometimes supported.
Cons
The company that has turned its great technical assets into good financial performance, weathering the Great Recession with a minimum of layoffs and other belt-tightening. However, that success does not seem to flow down to the rank-and-file. Salaries are decidedly mediocre for the industry, health care is very expensive (ERM uses a carrier that a lot of doctors seem to increasingly hate), and the company is terribly stingy with necessary and intelligent expenditures on things like IT, supplies, and training. This situation (and the absence of clear communication to the contrary) leads employees to the widespread assumption that the most senior partners take the lion's share of the profits for themselves, leaving a small pot to be invested in or divided amongst the employees who do the actual work.