I had the K95 before and also diiverse other Corsair keyboards.
The surface of the K100's tray is textured, which makes it very comfortable. It takes a while to get used to it. In any case, nothing "sticks", even in high summer. However, it is not that soft. It is when you press on it with one finger, but when the weight is distributed over the palms of your hands, it's different.

Extremely annoying with the K100 is the macro function or macro recording. It doesn't work as you would expect and Corsair support says "as designed". I wouldn't buy the keyboard again because of this, especially considering the price.