I've worn cool wings for two summers now, and I do notice a difference in terms of their ability to keep me cool. When I first put them on, when I'm sweating, when I pour cold water on them, all the time. The only time they don't help is when I'm stopped at a light in the hot sun, but under those circumstances nothing is comfortable.

They don't get waterlogged for me. In fact, after a ride when I take them off, the skin that was in contact with the cool wings is dry, while I'm soaked everywhere else, including exposed skin as well as whatever is covered by my jersey.

I've never tried a long sleeved jersey in the heat.