hey hun what size are you now?im about the same stats as you, i was a bog b small c cup and had 420 unders to take me up to dd/e cup. My sports bras are e cups ones an f, im happy with the size of mine but wouldnt of minded goin a little bit bigger, i think seeing the implant itself it looks huge but once its in your body its not as big as it looks. I would go for the 520cc as you dont want to go thru all that then get boob greed!xx