Pros
Excellent 401k plan, some very smart co-workers, immediate management listens to your aspirations and helps you achieve your goals. They hired me into a software engineer role with very little prior experience, and I appreciate the opportunity and the time in my current role. This varies based on role, but my experience has been that work life balance here is awesome. Every other Friday off, time flexing and I rarely need to work overtime and if I do it's typically only an hour or two here and there, YRMV.
Cons
Health plan is laughably poor for a company this size and they do not offer alternative options. Pay is below market for experience in the Denver area despite being told quarter after quarter how profitable the company is. Some employees are definitely here due to tenure and waiting to retire, it is the kind of place where you can coast if you are inclined, for me that's very frustrating. As can probably be expected everything happens very slowly here, from getting assigned to new projects to getting promotions.