UPDATE 11/14/19Wore these during a half marathon, they felt lightweight and provided a perfect fitted cushion for each foot, with this being the first half marathon I have done at race pace where I didn't have any rubbing issues (toes, ankle, anywhere). These will absolutely be the tool of choice when running half and full marathons in the future. Still leaving at 4 out of 5 since they technically are a little "heavy" for "ultralight" socks, but they are as comfortable and supportive as any sockSee full review