Hi there, I had 340cc from a 34b a year half ago, I ended up a 32e. I now measure a 32ff as I’ve gained weight. But for you I’d def opt for the 380cc, they dont ever look as big as you imagine them to look. You will prob end up a definate e cup, so go for the biggest. It weird cos my boobs look a dd in clothes but much bigger without, plus they measure much bigger too, but seem flatter than the real thing. Opt for 380!! even if you had 340 u would def achieve a decent size dd plus. Hope this helps.