The thing to remember is that XCR, Paclite, Windstopper, and ProShell all have the same breathability.

eVent (created by BHA Technologies in Kansas City, MO, a division of GE Corp), on the other hand, is the only other ePTFE available and the only one that doesn't use PU.

Jason -- Great writeup! The first part is consistent with my understanding that despite all the different names and successively louder hype -- the Goretex laminate is basically little changed over the years.

As for ePTFE that doesn't use PU, MontBell's Breeze Dry Tec laminate shares that characteristic with eVENT -- although the two are not identical.