Switzerland - Chocolate train, is it worth it?

I will be taking the Golden Pass from Interlaken to Montreux and am also thinking of doing the Chocolate train while in Montreux (goes to Gruyere and Broc). I also read that it is a similar route to what the Golden pass train already does. Question - is it worth doing the Chocolate train if I have already been on the Golden Pass or is it too duplicative for the time involved (full day).