I purchased this swimsuit along with the GabiFresh D/DD Cup Iridescence Underwire High Waist Bikini. I bought both swimsuits with size 16 bottoms (I'm normally a size 12) which fit perfectly. For the top, I ordered both a size 16 top and a size 12 to see what would work best. (Size 14 wasn't available and I was in between sizes, so I ordered different sizes to see what would work). I thought the size 12 top would work, since the size 16 was way too big. Unfortunately, the cups fit well, but because my ribcage is smallish, the band on the top just didn't fit for me - it was too loose and a tad too big, specifically in the section between the two cups.
To give you a visual, the cups fit, but if I lifted my arms, my breasts would be exposed from the bottom, which is not how the suit is supposed to fit. Mind you - I am a size 36DD, so it's possible that if you have a bigger ribcage that this could work for you. My recommendation is to order a few sizes to see what fits best, then return / exchange what doesn't fit.
Overall, the suit is made really well and I would still recommend it to others to try.