I asked the same question to the seller. He told me that there was no difference. MXWV2D/A was intended for the German market, MXWV2SM/A for Switzerland. MXWV2D/A would be delivered with the BS "BIG SUR", MXWV2SM/A would still have the older Catalina on it. However, my MXWV2SM/A, which is CHF 30 cheaper, was also delivered with BIG SUR!? 😲🤨