I own both the Golite Wisp and Ether WIndshirts. However, both are 2005 models, so I can't compare them to the pre-2005 versions.
I can say that I am a big sweaty guy who drowns himself in a poorly breathable system and I find the Golite windshirts to be pretty decent. I used the ether in the Smokies and Land Between the Lakes in 2005 and found it to be much preferable to the older system of "doing the best I could" with my rain shell (which by the way was a highly "breathable" ArcTeryx Paclite/XCR Goretex model - very breathable for a waterproof jacket, but only so-so for a wind jacket). I loved the Wisp in misty rainy conditions on the Colorado Trail this past summer. Far superior for breathability than my rain jacket. I do still get lightly damp, and the windshirts are only marginally water resistant. But its performance for breathability in cold wind is powerful enough that I don't mind breaking the dual-use principle by carrying one as well as a rain shell or poncho.