40D. After wearing sports bras/camisoles for years because I'm disabled and homebound, decided I was ready to try a wireless one. Was immediately happy with this, but at the end of Day One, my girls were VERY sore even though the straps were still comfortable. Almost gave up and glad I didn't.
Though the formed cups take a while to get used to, it's still better than wires digging into my underarms.

*As with sports bras, the band will ride up and the bottom of the bra kind of folds over and you will definitely have to re-adjust yourself in it a couple times during the day.