I picked up my 5990 1/A, my first Patek Phlippe ever, back in early June and as a massive AP Royal Oak fan, it almost pains me to say that the 5990 is my favorite steel watch I have owned in a decade. It has been almost impossible to take off! The watch sits on my wrist just right, the bracelet is so comfortable, and I don't have to think twice bringing it in the water with 120m of water resistance... not to mention the travel time and fly back chronograph. I am not sure if I would feel the same about some of the thinner offerings in the nautilus line because the thickness and heft of the case is what really sets it apart for me. I am genuinely surprised how much I have fallen in love with this piece in such a short period of time and it sure does make one hell of an argument for a "One watch collection"!