Pros
Uncommon Solutions puts great emphasis on their employee's personal and professional growth and even incentivizes employees to encourage that growth. They provide opportunities to advance in the company depending on the career path you want to follow - some engineers would prefer to remain engineers while others may prefer to move into management positions and Uncommon Solutions seeks to honor those endeavors even in situations where it may mean an employee will move on to another company.
Uncommon Solutions has an excellent balance of prioritizing customer relationships, business growth, and employee work/life in a way that makes it feel less like you're just another "cog in the machine" and more like you're contributing, learning, and growing which makes for a very enjoyable, challenging, and fulfilling job.
I'm especially pleased that they're willing to try new business methodologies in the interest of improving both the company itself and the work lives of their employees - if there are stagnant areas of a particular business model, they are very open to suggestions to modify and adjust procedures in order to better serve customers and employees.
Cons
The main thing that's been challenging for me is that historically there haven't been many consistent SOPs which can make it difficult for engineers to maintain workloads; There's been a lot of focus on improving this area and it's becoming less and less a problem but this is the other side of what I consider a good thing, the company is open to change but that does make it challenging to maintain consistency in SOPs