Verified Buyer Reviewed by Cy from PA on Tuesday, February 14, 2017
I've been wearing these for several years and the quality can't be beat. If you want pure warmth and lightest weight, go with a synthetic. Merino is heavier and not as warm, but is excellent for temperature regulation and defeating stink. I wear these mountain biking and backpacking. Merino wool in a mid weight layer holds up well to abuse-I find that lightweight layers of the material get holes within a couple of years under moderate use. I have three of these that are about three years old and still going strong. I'm 6'2", 230 pounds, athletic build. The large fits me like a true baselayer, more or less skin tight. XL fits like a light mid layer, with enough room for a t shirt underneath. Sleeves on both sizes are long enough for me. The quality on this piece seems the same as my older ones.