McFadden earned this spot by being a play maker for the Aztecs where he was named to the all-Mountain West first team three times. He also is a ball hawk who had 28 passes defended and eight interceptions in his career with three of those going for touchdowns.
What he brings to the Browns is that he is very good in coverage -- as a cornerback should be -- by being able to change directions with fluid hips, an eye to break on the ball yet still keep an eye on the quarterback and he is able to recover nicely if he somehow gets beat.
McFadden also is very good at disrupting the ball from receivers by getting a hand in the way of the wide outs hands or ball. Being a former wide receiver helps McFadden perform well in 50-50 chances as does his ability to get interceptions at a better clip than someone who has only been a defensive back.
The few downsides of McFadden are that he is not great in bumping or jamming a wide receiver at the line of scrimmage, and some of that has to do with him being just 5-foot-10. That size also gives him trouble trying to cover the taller and lengthier receivers.
The Browns need playmakers on defense and McFadden fits that bill, and if he is able to make plays like he did at San Diego State then he McFadden should see some playing time in Cleveland early on.
Here is a video of McFadden against BYU in the Poinsettia Bowl: