I bought this bra in both black and white, both size large. Super cute and I love wearing it! The fabric is nice.
I buy large because I have a larger chest size. I find that with mediums there is too much spillage at the top. That being said, the large for this one I found to be not very practical for doing actual activity. The straps would fall down my arm and if I moved around too much my boobs would fall out. I'm wondering if maybe for this particular bra a medium would have been better or if it's just the way the bra is styled? I've purchased other size large sports bras from Cheri Fit and they did not have this issue.
Overall though, I like the product and I usually wear it more as a crop top than a workout bra. If I am working out, I'll have another bra on underneath. :)