Pros
You get paid on time. If you land in the right team, many people are very pleasant to work with. Generally, it seems that people's hearts are in the right place; they simply don't have the training, wherewithal, or incentive to complete their duties effectively.
Cons
As an employee of a company that was acquired by Prometric several years ago, I have witnessed a slow, consistent decline in values, culture, and quality of product. The fact that the team at our prior company was so exceedingly competent shines an even less flattering light on Prometric. This company is riddled with staggering incompetence. Its lack of top-down empathy, its general apathy, its miserly attitude with regards to pay, and an aggressively unresponsive HR department speak more of Prometric's values that I ever could. Simple, well-justified queries to HR will typically be treated with silence or, at best, a milquetoast acknowledgement. The onboarding is laughable, typically consisting of random, off-the-cuff comments with no paper trail. It is the Platonic ideal not of "good," but "good enough."