Rado63
·Great problem to have choosing between two Pateks. Since you are asking for opinions, I will give mine. The 5040 has probably been more sought after by collectors for several reasons which is why if I had to choose one then it's the 5040. The watch is classically inspired. The Tourneau case 35mm x 42mm the Breguet numerals, and Breguet hands which makes a traditional dress watch. The watch also has a sigma dial and compared to the 5035, the 5040 has well proportioned subdials. The movement, the 240 Q perpetual calendar in the 5040, continues to undergo development and is in use today. Which means parts are available and perhaps if sent in for factory service there may be update to an older watch movement making it a good runner for a long time. I like that if I buy an older watch, parts are still available and perhaps updates available for it as well. The 5035 had the 315 S QA annual calendar which improved into the current 324 S IRM QA LU. The later reference 5146 is probably a better proportioned watch than 5035 as it is 39mm and 11.3mm thick and also has a more balanced dial arrangement. My .02, I would stick with the time proven classic 5040.