Pros
Work with some great clients. Your work has actual impact so the work is VERY rewarding. GSD has great benefits. The company has 30 year goals set out. The company is growing rapidly - the proof is in the sales. It's a relatively young company but has a solid structure in place plus all the best software and tools to track your performance and metrics. The company is metrics driven so easy to track your performance and takes out subjectivity. Lack of politics. A lot more job satisfaction and driven young team than working at a big corporate firm where there's tedious work to and a certain "amount of time" you have to put in before climbing up the ladder. At GSD you can work from home or anywhere as long as your get your work done so no micromanagement. They trust their employees unless you give them a reason not to.
Cons
The job is technical so you are drinking from a fire hose for a few months when you start -- so be ready for that but you will learn tremendously.