If 40mm is your sweet spot, don’t go for the 42mm. You will regret it. 40mm is also my comfort spot for most watches. I think the Optimum wears bigger than most Journes. It definitely wears bigger than the 40mm Centigraphe (my favorite FPJ) since the bezel is narrower on the Optimum. Ultimately, I parted with the Optimum even though it is a gorgeous watch. It just wears too big for me even though I am fine with Centigraphe and Perpetual. Good luck in what you decide.