Pros
Nice benefits, especially if you like to travel. Chill office culture, there's very rarely a feeling that you're under pressure to complete something. Developers are professional and good to work with. Completely flat structure of IT department. Meaning, every developer is pretty much equal and allowed to design features and make technical decisions. Success of a feature is determined by results of A/B testing. So you can pretty much work on anything and noone will tell you that your idea is wrong, especially if it's successful on metrics. This is great if you are full of ideas and feel that management won't let you run with them.
Cons
Other side of the same things. Flat department structure means there's absolutely no plan and no control. Everyone can quietly implement a feature that doesn't fit with the rest of the code. On the other hand, if they get noticed, they are immediately harassed by every other peer developer who has something to say. Getting people to agree on anything is practically impossible, because there's no authority and someone always has an opinion against it. Every code change has to run through time-consuming A/B testing, which creates huge technical debt and makes it really difficult to deal with it. All of this is viewed as a feature, not a bug; the company actually hires even more developers to run as many features as possible.