Pros: lots of room to grow, friendly/open company, casual workplace
Cons: busy, fast growing
Overall a very good place to work, but can be fairly busy most of the time as they keep growing and work keeps coming. Base pay is probably a bit low, but OT is paid for engineers (unlike many other places) and makes up for it, along with performance bonuses and the work environment. If you are looking for a 9-5 and in it just for the money, it's probably not the best place, but if you want to enjoy what you do, its a great option.
There is lots of room to grow into higher positions and management fairly quickly for those who want it. Because it's growing fast, engineers are forced to be driven and self motivated to learn, but it's a fun and rewarding environment with good mentoring. Lots of work is done between offices, but I've always felt at home when visiting offices across the country (we all work well together). Things have changed a bit since I've been there (nearly tripled in size in 7-8 years), but mostly maintained the same business approach.