Nice overall. Sleeves are a little wide. I like the fit on Calvin Klein a little better.

Update: After further use, I see benefits both for these and for the CK shirts. The CK shirts are little thinner and the arms are more fitted, which means that they are possibly better as traditional undershirts. The Lapasa shirts are little thicker and have looser arms. This makes them less well-suited to wear under a dress shirt, but they can be worn under looser shirts for additional warmth or by themselves. These are stretchy and the fit is fairly snug, so if you plan to wear them by themselves be aware that you should size up if you don't want a tight t-shirt look.