Pros
Extremely supportive, creative, and energetic work environment. Lots of kind, hard-working people who are very open to hearing new ideas. As a growing company, there's tons of room for professional development as well as the opportunity to expand each department, especially for individuals who take initiative. Management really cares about their employees, and are eager to listen, motivate, and ensure you're happy with your position.
The company also makes an effort to have a fun, social, and productive office culture, and there are lots of nice perks like snacks, good benefits, flex/vacation days, etc.
Cons
It's worth noting that they're a very ambitious start-up, so work can get extremely fast-paced with new tasks coming up all the time that require a lot of agility to deal with, especially since resources are often limited. While this is really great for growth (both for individuals looking to advance professionally, and for the company as a whole), it's not well-suited for those who find this type of environment stressful.