Pros
Most of the staff are decent people who are stuck in an unfortunate situation. If you're lucky to be paired with one of the very few lawyers (much less than half) who actually treat their assistants with respect, you will do well. The pay, bonuses and benefits are pretty good. Negotiate a better salary at the beginning though because while there are raises, they aren't anything exciting.
Cons
A very negative culture among legal assistants, most are continuously complaining about conditions but won't do anything about it. HR has told legal assistants that there is room for growth but there is absolutely not - don't buy into it. The only growth is after 10+ years, you may become an "expert" in a subject area, if they like you. HR is definitely on the lawyers side of any issue that arises and will not hesitate to use anything you tell them against you at a future date. If you want to make being a legal assistant your career and you are willing to work hard at it, this is the job for you. If you have any ambitions beyond that, look elsewhere. There is a moderately high turn over in both lawyers and assistants at this firm - you can sense the unhappiness in the environment. Gossip runs wild here.