Pros
The benefits are great (medical, dental, vacation time), the office has a lot of fun amenities like an arcade machine, dining area, common space upstairs, rock wall, you get unlimited 3d prints, it has perks like company paid vacations, beer in the fridge, you can bring your dog to work, free catered lunches several times a week, cool co-workers, and the company has a potentially bright future.
Cons
The lack of structure tends to inhibit progress more often than spur it (yes despite what people say, I did not see a single instance where a lack of a clear path and communication didn't delay multiple parts in a project), a few members of the team tend to be condescending when speaking (not sure if this is intentional or not), the pay maintains to be about 10-20% less than other places, while work hours tend to be towards the 60 hour range. There is also no raises, employee enrichment, or opportunity for advancement. The CEO does not acknowledge you when you say good morning, or say thanks when you hold the door for him. I feel like that disposition resonates with many of the people there as well.