The silver star of Mercedes, whether decorating the nose of a cute coupe or rather less cute tractor, stands for many things – premium price, quality build, and long-term reliability. Just as important are the marque’s rock solid residuals which, along with Fendt’s, are ‘as good as it gets’ in the world of second-hand farm machinery. Here we point out the strong and weak points of the firm’s MB-trac 900