^^^ +1, listen to Ryan here, he's got it right. If I could find it, there's an entire thread devoted to which is the correct way. Either works, but the more beneficial way is on the PCV line. I've actually seen people with two catch cans: one in the PCV line and the other in the intake/breather line. I didn't have any oil coming through my breather filter so mine is in the PCV line where it is definitely catching oil (damn thing leaks too).