..of preference on round case or Vintage 1945 case.. Very interesting. The revelations made me ponder if 1) there was any GP 3 Golden Bridge watch made without any Tourbillons 2) if the accuracy and winning 17 years holding records after submission to Neuchatel Observatory was a result of the Tourbillon or 3) The way the whole movement was arranged in a vertical order like Corum's Bridge. If the answer to 2) is indeed correct, then we can safely say Tourbillon does have an effect on accuracy .... but dont forget, the 3 Golden Bridge arrangement of the mechanism resembles that of a pocket watch and thus, the tourbillon has the most positive effect...