I like the second one. I ordered a variation of the first one and it fit terribly! I'm pretty small on top but I always get L from f21 just because I like my tops to fit loosely and even in a large the top was skin tight and also very cropped. The one you posed is a little different from the one I ordered so it might be ok but I just thought I’d warn you.
I love both of them! I order from them pretty frequently, but only things that are kind of trendy and I won't mind if they die on me quickly. That, and their long t-shirts which are $6 so I can always afford to buy a couple more in whatever colors I need. I think their shipping time is pretty average but it's really amazing how much they can fit inside little boxes. I always think they sent half my order, but really everything's just rolled up so well.