I'm an adult but was told the larger sizes would still fit. So, I bought the bikini top and bottom.
When I put on the bikini, I found that the top fit perfectly, while the bottom was a bit too small. I could still wear it comfortably, and the bottom kept my "parts" in place very neatly, but I thought it exposed a bit too much of my pubic area. Also, I found out that I wasn't secure enough about my body to be showing off my belly. I know I could have returned the items, perhaps to swap them for another size, but I already had to pay €17 import tax to get the items into Europe on top of the delivery costs, and I didn't want to risk that again.
Instead, I decided to keep the bottoms, but wear a swimming suit over it. This way, I had all the advantages of the RUBIES bottom, while still wearing something that I was comfortable showing to other people. I've worn this combo for swimming a few times now, and I absolutely love it! It's a bit of a shame that I have an unused bikini top lying around here, though.