Pros
Lots of flexibility. No, or at least very few, "standard" regulations to work around. Some jobs, including mine, gave a lot of exposure to full product life cycle, and made you feel like you actually owned what you were doing, not just a cog in a wheel, like many other big companies. Benefits were good. Good place to work if you already have lots of experience, and a strong (And truthfully, sarcastic) personality with a good sense of humor. Must be willing and able to drive everything yourself, and plan for lots of push-back everywhere. It's not a problem if you are prepared for it.
Cons
Pay is low for comparable jobs. The flexibility and regulation free atmosphere makes communication poor, and unless the one doing the driving already knows all the expansive list of things they need to be doing and thinking about, it wont get done and will cause problems for everyone else. If you are new, the training will be barely there, and you just have to figure it out yourself. You will be quickly judged on how you handle that, and that opinion of you generated will probably never leave; even after you get better. I've seen it happen a lot. My personal recommendation is that this is a great place to work for those with the know how to drive a project from ideation through full implementation. Those that are not timid, and know how to get it done. The pay isn't amazing, but if you are at a point in your career that you can do the above effectively, you have probably already paid your student loans off, and can afford the trade off of lower pay vs. a flexible employer with a great culture and ownership of work product. And last point: it's hard to grow here, so I echo the same concern of "most" early career employees may not like it here. All depends on who you are and what you are willing to do. Many employees stay very late. Its never a requirement, and I really mean that, but if your trying to climb the ladder, the grade is steep.