You may have heard the news that IWC has released the limited-edition IWC Ingenieur Chronograph Sport Edition “50th Anniversary of Mercedes-AMG” to commemorate, as the name suggests, the golden anniversary of AMG, the performance motoring arm of Mercedes-Benz. The watch will be available in a limited run of 250 pieces and is available at only a small premium over the standard Ingenieur Chronograph Sport.
Under the dial, this watch is equipped with the same movement as the regular production IWC Ingenieur Chronograph Sport or the Portugieser Chronograph, which is the in-house Caliber 89361. An automatic chronograph shared with 68 hours of power reserve, this movement provides flyback functionality, a feature that fits correctly in with the motorsport racing theme as it is used to time successive intervals of time like race laps. It has the special hour and minute totalizer as well at 12 o’clock which is intended to make the chronograph reading more intuitive. 
One of the differences between this 
I said before that this edition had an especially light premium over the non-limited model. Special edition replica watches often cost importantly more than their standard siblings, many times with no other reason than that it is labeled a special edition and maybe has a different dial color – and for some supposed “exclusivity.” This can be quite frustrating for watch collectors.