Pros
Unlimited PTO (although they constantly watch the numbers and make you feel uncomfortable taking it), Freedom - you can walk around, go run errands, etc; nobody really cares as long as you get work done, Time to time you get to work on cool projects.
Cons
Very poor middle management that receives no training - if they can't adapt, they're let go quickly. Horrible work/life balance - they say they don't want you working over 40+ hours but you constantly work 60-80 for little to no thanks. They make you feel like you absolutely have to or you won't have a job. The seniors are in denial that people aren't happy. If you walk around as an employee and talk to other employees, they'll all tell you the same - but probably won't ever get to the seniors. It's a replaceable cog system. They have very talented people working, but when it comes down to paying what they're worth and giving them a good work environment, they'd rather just let you go. I've seen it over 30 times. We all have.