It seems like a high quality undershirt. I'm giving it 4 stars, though, because my husband says it is a little too long and so he would not want it again. He is 5'10.5", of medium built, and took a medium. Perhaps it will shrink a little in the wash.
Great t-shirt overall...
Love: the length, the sleeve length, the neckline, the feel and it seems to be of high quality.
Don't love: really hugs the body (if you're an L normally, order an XL), shrinks almost a full inch in length.
Overall, I'd say 4.25 stars. If you don't have a perfect body this is fine as an undershirt, but you'll never be able to wear it on it's own. It does shrink a bit, so beware of that.