Pros
First off, the product is the coolest of the cool in the 3d printing universe and is worth taking the job (especially if you're a 3d printing nut). The technology and design of the printer makes everyone from little children to older engineers drool with excitement. For the most part, working there was good. The job "perks" more than make up for the relatively average pay. The flexible schedule and vacation is a major plus, as well as the free food and the twice-yearly company trips. The environment is open and collaborative and most of the people that work at Formlabs are extremely knowledgable and passionate with a diverse range of interests. A lot of the people I've met at the company will be life-long friends. And even though the work is not the most creatively inspiring, I do feel like I've learned a lot technically, but also learned a lot personally that have improved my abilities to work well with others and collaborate as part of a team.
Cons
Not going to be the blind idealist when it comes to the cons. There are the typical growing pains occurring now that are common among fast-growing startups. The lack of defined roles and responsibilities worked well when there were 20-30 people but now that there's significantly more people than that, it just produces confusion and even some animosity between coworkers at times. I'll tack on the lack of communications between growing teams can be difficult and sometimes leads to having to repeat work several times over when it could have been done in just one. Both of these "cons" contribute to painfully slow decision making that would more likely be found in some government bureaucracy. Now onto the Formlabs specific cons. Management doesn't seem to understand the concept of work being "cheap, fast, or good. Pick two." They always want all three. Rarely enough time is given to explore options in depth and create truely great work. Management also has a bad habit of being stingy with resources and money, leading to corners being cut that bite us in the a** later on. There have been some questionable hiring decisions made in the past, usually due to the rampant MIT/Media Lab nepotism. And lastly—and this is a biggie—now that Formlabs is bigger and maturing as a company, there are not many risks being taken creatively anymore. Sure, we could spend less time and money doing this stuff the "average" way, but why don't we shoot for this stars and create something that could surprise and delight our customers? It makes my job more exciting, the product more exciting and our customers more excited. At the rate they're going, if you describe yourself as working in a "creative" field, there are probably more exciting and creatively fulfilling jobs out there.