With the Nike sports band with all the holes in it, it wasn't too bad in terms of comfort in very hot (95F), humid weather. I had worn the Milanese in hot humid weather and it was great. Better than the Nike sports band IMO, but with the Milanese band it has to wrap around your wrist completely. With the sports band I can wear it loose as long as the sensor is touching my wrist. So while the Nike sports band doesn't feel better than the Milanese on my skin in hot humid weather, I can wear it much more loosely than the Milanese. I also think that the thicker AW2 allows me to wear it more loosely than AW0. How's your watch band in hot humid weather?