Hi Sue
I was a 34b size 8 and 5ft4. I had 380cc overs 6 days ago,so far i am easily filling a 34dd sports bra, they are already taking shape and softening up.
I have been told by alot of people that the size suits my body and shape and that i look really good with them. I tried doing some pics the other day but unfortunately my camera is broke. I think the 340 will look fine on you.