Applying with a recruiter is a lot different than going directly to the employer on your own. Recruiters are more likely to have information about the company's needs, the competition, and what to expect in terms of benefits or salary. They could already have a strong relationship with the employer, which raises your chances of getting selected.
However, not all recruiters are the same. It's important to seek recruiters or recruitment agencies that specialize in your field. Find out what they can do for you and set goals with them early on.