Pros
Really energetic and vibrant company with really well rounded and talented peers. It's fascinating to work at a company that has tripled in size since I joined and has a lot of really cool products on the road map. We bolster businesses in a really positive way and receive encouraging feedback from our customers. Offices are a little sterile, but very nice. Great benefits and perks (especially if you like coffee, smoothies or free food). Transparency is excellent. It's refreshing to know what our finances look like, what's on the product roadmap and why decisions are made. It helps promote accountability and gives me the information I need to do my job. The product leadership is great -- we set ambitious hardware and software goals and generally get things out close to deadline.
Cons
Career advancement is a bit difficult. The company structure is very flat, so if you want to lead a team someday, odds are that's not going to happen. However, if you have an idea or something you think the company should be doing, you can add it to your role and put together a project team to help you. It's just hard to ever get to a I-Have-Direct-Reports position if you aren't hired directly into one.