No one else will take it and the game will never begin until he buys it. It's greatly desirable for the Sx owner to have M3. M1 and M4 owned by the same player are much more valuable than owned separately. The order of value of the Minors is approximately 2,4,5,1,3,6. This has been the start for several of our four-player games.
Player one is in a very good position.
He begins with the best income and has M1 and M4 working together. He'll end up with the directorship of the Baden and have prepared their track for them in advance. If, heaven forbid, player 4 doesn't take the Pz, player 1 gets a free tile lay on the first turn of his directorship, too. The next best position is player 3. Player 2 is in the third strongest position.