Its been a warm fall but have had an opportunity to wear these a few time in early morning rides. Coldest so far has bee 50 degrees. Perfect for temps from 50 to about 65. Im 58 155 lbs. no bunching, with a size medium. Dont even know they are there. Would certainly recommend them. Will try them when the temperature drops below 50 but think they may be a little too light.
Gore Windstopper arm warmers are the best that I've used. They stay up, unlike every other pair that I've had. Like a windproof second skin, they keep the wind out yet breathe very well. They are ideal for high-mountain cycling.