As you know except VLS everything else displayed on PFD comes from flap lever. They are your good time friends. The moment there is a mismatch between lever and actual surface the displayed S, F, VFE and VFE next are incorrect and only mislead you. So we ignore and don't fly them by selecting speed. The new way of configuring is given in Landing with slat/flap procedure in QRH. If you do not refer to QRH then how would you configure? ECAM doesn't tell you that. QRH Vref addition sometimes is slightly different(should not be) in that case you can take the higher. Eventually you will be flying the displayed VLS as it is always correct.