I couldn't decide between this shirt and the similar N3601 all-cotton version.  So I bought one of each.  Now after one wash and one wearing, I'm able to report that they're both good shirts and indeed similar except for the fabric.  For my money and body type (tall and skinny), the all-cotton version is the winner.  Maybe not as good as the old American Apparel shirt of same kind, that you can't get any more, but quite good -- comfortable, light but not too light, close fitting but not snug.  This blended fabric one is too clingy, especially in the lower arms, while the section where the arms meet the body is way too large.  The neck is too wide too, and though I don't mind that as a style it doesn't work well with this shirt.  Naturally everyone has their own body shape and preferences.  Maybe this one will work for you.  Meanwhile I'll take the cotton one -- and save $4 besides.