First, as a queen mattress topper, it definitely fits a queen sized bed. Others I’ve had haven’t fit properly and Serta’s does, so that was a relief. It also stays in place. No movement on its part. It was a tad thin, but there’s no doubt it was at least 2 inches like it said it was, so you’re getting what you buy. As for cooling effects, I’m not too sure just how cooling it is. It’s cool here presently so I don’t know how much to credit the topper and how much it’s due to the weather. It’s comfortable enough, just unsure how much difference it actually makes