Pros
Amusing to watch telephone tough guys pretend they're real "players" while they read prepared scripts to client companies and waste candidates' time with bogus job postings. It's entertaining but after about a week you realize what a bunch of frauds they are and can start marketing yourself to other companies (while removing RHI from your own resume).
Cons
You don't want any involvement with RHI on your resume. If you make the mistake of doing business with them in any capacity (as a candidate, client or employee) ensure it's very short term then move on. If you're a candidate, you need to understand their job posting are FAKE. They post them to get you in the door and talk about where you're currently working and where you're interviewing so they know where to market themselves. Don't believe me? Go look at their job postings today....then take another look at their postings 6 months to a year from now. There's a reason they look the same...because they are the same fake job that doesn't exist. Look for buzzwords and cliché phrases like "huge upside potential" and "rapidly growing". Been using that garbage for years.