I have the first one and I really like it. The material is thin, but not see-through. My only problem is it seems like the necktie is going to be really hard to keep from wrinkling, even when it's hanging.
I think Anthro carries this Porridge tee in several different patterns, and the ones I've seen IRL are very thin cotton and run small. They are really pretty but some of the ones I saw in the store were pilling so I don't think the quality is that good.