fit was big but small through the shoulders? I'm athletic 5'8" 165# seems the med should have fit.

These do fit snugly (by intent), so if you want a loose fit, you should probably order a larger size.  They worked great and we used a lot less sunscreen since the torso and arms were completely protected by our shirts.

I'm happy about product and shipping it so fast

I used this under my short sleeve wet suit when the water was colder.
It did what I thought it would and that was to keep my arms warm.

Trim but comfortable, it doesn't pull or constrict you in the water at all.  Kept me protected from the sun in summer Barbados heat surfing at Soup Bowl.