I bought this for my son who is a Boy Scout and camps every month all year. I specifically got it for him to wear on a 7 day canoeing trip in Canada where the bugs apparently are so thick they look like clouds. He said this was very comfortable and helped keep the bugs away. He didn't use bug spray at all (and he had some) and had no bites when he got home (he also had the insect shield pants).  He said he either layered this with a long sleeve shirt or wore it alone, depending on the weather.
He has since taken it on every camp out. He is 6'1" and 210 and I got him the XXL. He could have worn an XL, but he like his shirts long and a little loose. Will be buying my younger scout one for next spring/summer camping season also. Highly recommend.