Pros
Robert Half is a large company with an international presence resulting in many opportunities. Robert half has a well oiled machine at work finding clients that need the service of technical professionals.
Cons
Applicants fill out all of the normal paperwork of a W-2 employee including a non-compete before having a first assignment. A naïve new applicant can be left with the impression of being more obligated to RHT than they really are after signing an employment agreement and non-compete. If an unreasonable executive at RHT in a specific market was inclined to enforce the non-compete without ever having placed the applicant would be in an uncomfortable position. The executive would in affect be bringing the money and credibility of a large corporation to bare on a single person who has few resources relative to RHT. A nuisance suit by RHT could be difficult for a young professional to defend themselves against.