I ordered one of these in Medium because I'm very slim and it was tight around the torso but loose around the arms but that's just because I'm a slim person. I love the mesh underarms. I was hesitant to buy it because I thought the underarms would be a different color but it's all the same color. Got it in ACU Tan and it's great for working out. Unlike Under Armour it wicks away the sweat. But yeah it is very tight and hard to get on and off. But tight doesn't exactly mean bad. I kinda like it because it feels like a second skin.
Better construction, look and feel than UnderArmour. They are very tight, so order a size above you if you dislike tight clothing, though tight isnt bad...
The LE Tight Crew is way too tight. Even went two sides up and it was STILL uncomfortable. The 5.11 shirts have better construction than Underarmour but the 5.11 shirts are way too tight. I tried a 5.11 Loose Crew Shirt #50007 and it feels much better under a vest and that is what our platoon is now wearing.