Pros
Get ZS tag on resume. If interested in pharma/healthcare/lifesciences, being at ZS for some time can help a lot in the long run. Immigration policies are generous, readily sponsor H1B visas and Employment Green Cards. HR Policies, Benefits (that are generic to the whole firm) are great Office culture at most US offices tends to be good. Helpful, good-natured, hard-working people.
Cons
Policies related to the CIG track have changed somewhat, but there is still a long way to go to improve things. Managers in client spaces where CIG is present continue to exploit CIG A/AC's (sell projects with CIGs staffed where CIGs have to do typical business consulting work) Compensation (basic, bonus) significantly less than peers at the same level in other roles at the firm. Can feel discriminatory, especially when CIGs work together with non CIGs on same projects. Staff augmentation role ~ can get isolated by its nature