Have you worked with a third party recruiting agency?

I have worked with a few recruiters, in two fields: regulatory affairs, and data science.

The regulatory affairs recruiters would negotiate with the company on your behalf, and, for my friends who got hired, they would go through their current contract line by line and negotiate the crap out of the hiring company, until you got lots of perks in addition to a great salary. When I worked in RA I probably had a half dozen recruiters reaching out to me every week, the situation for RA is kind of crazy because of a bunch of new regulations with upcoming big deadlines.

For technical/data science recruiters, I have gotten a few interviews, and they have generally been pretty good about framing my experience and prepping me for interviews. One recruiter reached out to me via LinkedIn from a small agency, I reached out to one recruiter who helped a friend of a friend, and I reached out to Tek Systems because I had heard good things about them. For the small one that helped a friend of a friend, they wanted to meet me in person and they gave an interview that day with a hiring manager who they thought would be a good fit. I am hoping that as my career advances the technical/Data Science recruiters will be a little more like the RA ones.

Not successfully. My current position is my first in the industry and I've been here for five years. I interviewed with other companies before this one and since this one and almost all were through a recruiter. I've not a had a bad experience with recruiters, although agencies can have some really crap benefits if you are talking about contract to hire positions. Some of them that I've see are $2k/mo benefits for a family and they don't start for 84 days (the other policies were not meeting federal standards.

All of the recruiters that I've used were working for the company. The only one that I've ever found that worked for the job seeker cost around 1500 USD. I would really hope that they are worth it, but I didn't have the money on hand to do it.

My experience was fairly negative. I should clarify that I live in the Netherlands, which is probably rather different than the US (salaries are much lower at least). All recruiters were paid by the employers in some form and they all contacted me after I let my CV someplace (linkedin, jobsite etc.)

Now to answer your questions:

• I first got matched with the large well-known corporations who offer nothing interesting (banks, secondmend etc.). It should have been very clear from the start that these were not interesting to me. I guess they pay a higher fee to the recruiter. Only after I refused several offers from such clients did they allow me a peek at the stuff I couldn't find myself.
• I don't think I've ever needed more visibility for the kind of jobs recruiters have.
• When it comes to negotiating employment terms, I feel I'm better off without recruiter. One once called the nationally average salary I was asking "ridiculously high". Companies are more willing to pay you more if they don't also need to pay the recruiter that introduced you.

One interesting thing that happened: there was one job I applied for through a recruiter that seemed interesting (after many total misses). Unfortunately the company turned me down... for a job I didn't apply for. The recruiter urged me to call them to ask for clarification, which I wouldn't otherwise have done, and they did eventually offer me a position. I did turn it down because of the whole chaotic ordeal though.

In short: I would never recommend working for a recruiter that contacts you. They just see you as a product to be shipped. Much better to attend interesting meetups where you will find the companies that share your passions.

Thanks for all the replies, y'all. I appreciate the knowledge share.