Well, let me qualify that a little. Various makers have conducted extensive testing of their products. The Gore folks, for instance, have tested their fabrics against others at the Hohenstein Institutes in Germany, a renowned fabrics laboratory. But I'm not sure what any of it means to the average user, at least in terms that make sense. And, I tend to be skeptical of tests arranged by Company X to show why their stuff is better than that of Company Y. You can be assured that only the most favorable results will be released. No truly "independent" entity, at least that I'm aware of, has contracted with Hohenstein or other labs for truly "independent" results. I wish the military's Natick labs would weigh in on thisthey test all sorts of clothing for use by our armed forces, and have no ax to grind other than finding what works. For what it's worth, the military uses a lot of Gore-Tex.
I will say that in most tests, under most conditions, Gore-Tex (and in particular, their newer-generation XCR) works better than most other waterproof-breathables. My own purely anecdotal experiences tend to support this. What you have to determine as a consumer is whether the relatively small amount of additional comfort gained from a piece like The North Face's Mountain Light XCR Parka ($349; www.thenorthface.com) is worth that much more than something like REI's Ultra Light Jacket ($125; www.rei.com), which uses a proprietary coated fabric called REI Elements.
The wild card in all this is a relatively new fabric called eVENT, which is chemically somewhat similar to Gore-Tex. However, it goes through a different manufacturing process that results in a material with more open pores than Gore-Tex, yet one that still retains waterproofness. Lowe Alpine uses eVENT in several garments, including their new Evolution Jacket ($350; www.lowealpine.com). I've been wearing a cycling jacket from Pearl Izumi made out of the stuff, and I love it. But I also loved Gore's Activent fabric, and when it couldn't find a market it went away. I hope the same doesn't happen to eVENT.