We like to do things properly at PisteHors.com and that includes gear reviews. No 30 minute test on the mountain during a layover on the London-Tokyo red-eye then a quick article pimping the virtues of some flakey new product. Oh no. These skins have done about 100,000 meters climbing and this is what we think.
Glueless skins have been around for about 5 years. The bottom of the skinis coated with silicon. The surface of the silicon looks like thousands of tiny cups that stick to the ski via suction, like a Gekco's feet, hence the name. Now a lot of skiers don't believe these can work, but they do, and pretty well.
There are a number of advantages
However, at least with the Geckos we tested we found that the skins were less durable than the Colltex and Black Diamonds and G3 we've used previously. They were prone to nicks and would wear on the edge more. In fairness they were about half the weight of a pair of Black Diamond's industrial carpet skins! There is a another issue, the silicon will slowly come off the skin. Some people have complained of residue being left on the base of their skis, this seems to be an issue with warm conditions, maybe skins left on in an overheated alpine hut? We never saw that but areas that are bare will no longer stick, principally at the tail and edges. Now this provides an entry point for snow and slowly the skin will become unstuck from that point. Unlike skins with glue, it is normally a case of cleaning the surface and warming the skin for about 10 minutes to get it to restick, however once you've suffered this on a tour they are likely to come unstuck again. Very annoying. The solution is to remove the few cms of material without silicon on the tail, we've done this twice shortening the skin by some 5cms over 4 years. Related to the problem of skins not sticking on a tour is humidity, they don't like wet conditions much, touring in rain or crossing rivers are not their strong point.
There are a number of manufacturers offering glueless skins in their range. Residue left on the ski base seems to be an issue with some and the formulations vary from season to season so your mileage may vary. We were using the Black Geckos but are currently testing the newer Red Geckos. More later.