Pros
The first thing that strikes you when you join Mos is how friendly and warm this group of people is. Even the more serious-looking ones are super empathetic and kind and make you feel welcome from the very beginning. They are also a very principled bunch with a strong mission and they put an effort in making sure new team members share this vision. The product might seem simple in appearance, but makes you feel you are actually adding something good to the world. No small feat if you ask me. A very horizontal structure, lots of communication, everybody is heard, feedback is well received. Still early stages so there's a lot of change, experimentation and processes being defined so if you are willing to be part of these kind of things, this is a good time to join.
Cons
The amount of communication and social interaction expected can be a bit overwhelming if you are more of an introvert type.