Pros
ACE is an entry level position that incorporates training. The training involves acquiring certs as well as on the job training with Senior Consulting Engineers. CDW works with you to improve yourself and define your career path. Fantastic culture and access to several training resources. In most cases you'll be working from home which was a huge pro for me. Work with top clients on the latest technology. In addition to that you'll also receive great compensation, including a quarterly bonus, and benefits. It sounded too good to be true but it wasn't.
Cons
I don't think this is a con but it might be to others. Depending on your skill set you may have to put in extra hours during the ACE program to grasp the technologies you are learning.