Previously, Cook was solely a staffing company. As the direction of the company changes to that of a resource provider, growing pains are some times a part of the process. With more and more internal employees (instead of all contract workers), the company is working on finding it's way with employee policy. Entrance requirements to the FastTrack'D program are constantly being tweaked and evolving. Not necessarily cons, but worth mentioning.
Compensation isn't exactly spectacular when you first start. Career changers with a family to support may find the first six months to a year tough. Though I will say, the pay ramps up nicely and I've had no issues with what a previous reviewer mentioned as "unrealistic metrics and expectations".