My '71 P15 Paramount tourer came with one. It did the job, but not very well. I replaced it with a Rally which shifts much better. Some say the Rally isn't all that good either compared to a SunTour VGT-Luxe or a Shimano Crane GS. I agree with with CV-6 on this one. If you need one because it is the correct part for your restoration, go for it. Otherwise, the SunTour or Shimano are generally cheaper and far better. You probably know this already, but the Gran Turismo is a wide range derailleur for touring which is why I mentioned the VGT-Luxe and the Crane GS. If you don't need the wide range, don't bother with a touring derailleur. The short cage derailleurs will usually perform better than the long cage ones.