Bypassing recruitment agencies?

Hello,
I have recently applied for two separate positions via two recruitment agents. Both agents have also suggested applying for a third position at another company.
What worries me is that they've both said they're the sole recruiter for the position, and they've both insisted they've been successful in placing various other people in these companies.
When applying for a job through a recruitment agent, is it also wise to apply directly to the employer, if I know who it is?

I don't want to cause issues for the employer, or the agent if they're legitimately recruiting for the position. My concerns is that the recruiter merely trying to solicit the company with my details, and wanting a fee for them potentially employing me.

Has anyone had much experience in dealing with recruitment agencies?
Thanks for reading.

I think what you really need is confirmation that there actually is a vacancy. In my experience, when there isn't really a job and they are just soliciting with your details, the agencies will only be vague about the 'job'. If there is an actual vacancy they will be able to supply you with a job description, details of benefits, salary, and other information, or if they don't know the answer to a question, will be able to ask. Ask them lots of specific questions, don't allow them to put forward your details without knowing which specific job you are applying for and without seeing a job description.