Haven't worn them yet, but I figured an objective test is the best. While they were on the clothesline this morning in full sun I stuck a probe thermometer inside the shorts, up against the fabric, on these and several other pairs of shorts.

It's hype.

What was interesting was that the fabrics with a matte finish were a few degrees cooler than the shiny black ones. Which wouldn't necessarily translate into *feeling* cooler, since they might not vent/wick sweat as well. But the Coldblack shorts were comparable to the two other pairs of shiny black shorts I had on the line ... three degrees cooler than one, three degrees warmer than the other.

Don't waste your money. I got the shorts from an overstock site, and they still weren't cheap, but not out of line for some of the other features I was looking for, but I wouldn't pay extra for the Coldblack.