I live in Australia, notorious for it's extremes of heat, drought, & all things brutal weather-wise. I have kilts ranging from a 5yd acrylic SWK through 13 & 16oz tanks up to 18oz military tanks, & I can honestly say that I feel no noticeable differnce in comfort level (other than the better hang & swing of the 9 yarders). Heavier generally wears better, retains pleats better, & has the advantage of being warmer if the weather DOES turn nasty!