They have no doubt produced some amazing watches (the gyro's spring to mind) and their Reverso's are absolute classics, but I am not sure they could be defined as 'best' in terms of quality. F.P Journe is also producing some incredible stuff, but they haven't quite broken into the realms of Lange and Patek with PC Chrono's and Tourbillons. After all, it was Philippe Dufour who said the best chrono in the world was the Lange Datograph.