Just found this article that explains just about anything you'd want to know about rain gear.
http://indefinitelywild.gizmodo.com/rain-jackets-explained-1711511848?google_editors_picks=true
Bluegrass
06-18-2015, 16:12
As a follow up, here is Andrew Skurka's take on rain gear: http://andrewskurka.com/2015/backpacking-clothing-rain-jacket-rain-pants/
I tend to agree with Andrew - in warm, humid environments like the AT, breathable waterproof fabrics will retain moisture inside and you will get wet. It is just a matter of time, with the time depending on a large number of factors including weather, activity rate, and specific fabric.
I tend to find myself gravitating towards well-ventilated rain gear. Larger pit zips, for example, would sell me on a rain jacket much more than a new fabric.