I get to send my resume to a few recruiters and they call me with all the openings that fit my skill set and i would be interested in. They make looking for a new position so much easier. Often they work in teams so you get multiple people doing this for you at the same time. Plus you build a relationship with them, their team, and the company so you with them better next time too.
They are invaluable.
I do have to say though that there is enormous variability in their skill. The secret is to only work with a few that have access to different contacts and that you trust. Don't spray your resume out there to bad recruiting companies.
I have noticed a difference between industries though. In my main industry (finance and financial technology) recruiters tend to be very knowledgeable and work very diligently to give you leads that fit your skills and priorities. I've noticed that in other industries like web or internet start up they can be atrocious. I get all sorts of random crap from them so you probably need to be extra careful in certain industries.
But i would never give up my recruiters. They take a lot of pain out of me trying to find a new position.
I have a lot of love for my recruiters. I wouldn't have nearly the career i do now without them.