At size 30 each 100 cc of implant will correspond to 1 cup size change. The 474 mL you measured corresponds to a size E. The answer to your 1st question is the more volume added to the breast the more the breast will displace with motion.
30C natural breasts tend to be relatively perky since they are not heavy enough to cause significant sagging. Although 30C breasts may look somewhat large on a woman who has a small frame, the overall breast size is not considered particularly large so some women with this size may be .
30D Breast Size is one of the most desired bra sizes around. Here's our ultimate 30D cup breast size guide, photos & comparisons, only on HerBraSize. 30D breasts are usually look relatively large considering the small frame of a woman with a 30 band size, but some women with this size may consider getting implants if they prefer to have a.