Steven -
My valve cover breathers leak a little, too. I placed both of mine
to the rear for appearance sake. They are Billet Specialties (to match the pattern on the valve covers - the only ones I could find with any kind of a linear pattern). They only leak during "high performance driving", so I suspect that even though I have a baffle plate beneath them (the ones that come with the Motorsport high rise covers), the
oil still get sloshed by g's and centrifugal forces against the rear of the covers and then out through the breather holes. You might have the same situation. I'm not too worried about it.