Pros
Trellist has a team environment that is very project oriented. Anyone entering the company can have an impact on both a project's success as well as the company's direction. Trellist is extremely social and geared towards company events. There is the opportunity to learn as well as explore new professional avenues. Hard work is expected but success is well rewarded. There is the opportunity to establish long term relationships which will enable your career going forward. The leadership is very focused on the employees well being and tries to foster a friendly work environment.
Cons
The work can be demanding though typically the hours are not overly long. You need to think like an entrepreneur, while this isn't ideal for everyone, if you are this type of person, it can be a great fit. There are many long term clients, which is a plus, but this can translate into ongoing work which some people find less interesting. The plus side is that requests for new work are typically honored over time.