I have not seen the shoes yet, but they claim that the innovative plastic shank does not need breaking in - the arch is flexible right out of the box. Another unusual feature is stretch material over the heel to avoid wrinkling. The big advantage of Siberian Swan is that they offer so many customisation options - vamp, profile, shank strength, width and heel. You can even order them in a variety of colours and in matte finish!
Check the fitting instructions on their website for more details.
Read the comments below for more detailed information from fans of the shoes.