Pros
People-focused, great organization and culture. Tons of opportunity for training, certifications and career growth. Excellent reputation both from vendor relationship as well as customer. I found the company to be extremely flexible with work/life balance and the bonus structure is outstanding. Many people stick around with this company for a long time and there is good reason.
Cons
As with any IT service provider the biggest disadvantage is cross-competing vendors and products. There tends to be less focus if you're a Microsoft-centric IT pro.