I am a Gore Mountain Tech member and have had the prior version of the Gore Bikewear Xenon Gloves for 2 years now. I use several Gore products and do so when I need a product I can rely on to protect me from the elements. I live in the DC area and commute an hour each way through the winter. I was looking for a glove that wasnt bulky but kept me warm. These gloves do exactly that. The Windstopper protection keeps me warm into temperatures reaching the teens. Keep in mind that I am on a road bike creating my own 20mph winds as well.
Once in the teens you can begin to feel some of the cold so at this point it becomes necessary for further protection. These gloves dont have any other insulation other than the Windstopper fabric. I would highly recommend trying the new Thermal version of these gloves. I think that would provide a step up in protection without adding much bulk. I plan to test them out ASAP. Another option to adding protecting is slipping a liner on underneath these gloves.
I have also used these gloves in Adventure Races where we spend an entire night in the woods and on roads sometimes in very cold conditions. The gloves again provided protection to a certain point where more insulation was necessary.
Highly recommended and worth the cost.