Pros
HSG is dedicated to the vision of a world where people are understood, and that comes across in all aspects -- the product, interactions with the client, and especially an internal focus on understanding each employee and how everyone can best adapt to each others' styles. This is something very unique to the HSG culture that I have not experienced elsewhere. The CEO's passion for the cause shines through, and is mirrored in each team member's dedication and strong work ethic.
Furthermore, because HSG is a small, young company (although completely profit-driven) there is a lot of opportunity to make a big impact, grow, and gain exposure to a lot of responsibilities and opportunities that you would not get elsewhere. On my third day at HSG I was sitting in a sales meeting with the CEO of a Fortune 500 tech company! If you are looking to help build a cause-oriented company from the ground up, this is a great place to be.
Cons
The cons are what inherently comes with a smaller company -- less infrastructure (but also less bureaucracy and more flexibility).