I read most of the reviews that said size up and that certainly worked for me. I finally wore them and they stayed on and did not budge all day while on vacation. I never felt uncomfortable and completely forgot I was wearing them. They do however gave me a slightly odd shape but that might just be because Im still figuring out how to Place them or I might have needed an extra size up. I am in between a B and C for reference depending on bras and ended up buying the C double. I wouldnt suggest skin tight thin fabric shirts with this I imagine youd be able to see the lines especially if they're not a proper fit.