Good place to buy from is Bravissimo, where a good range of styles and sizes is available and there is no problem changing them if the size is wrong, but you do have to know your size first. However, I totally agree with what you say about the different makes, Fantasie is good for me, but Panache is totally wrong and much smaller . If the back size goes up, then the cup size should theoretically go down and vice versa. Also recommended is to be measured in a couple of shops, therefore the correct size will be definite.