Hey there,
I am 19 years old, so I thought I would chime in. I actually rather like the Calatrava, especially the 5196. I think the 5196 conveys a sense of modernism while still being quite classical in composure. However, I first became enamored with Patek upon seeing the Golden Ellipse (3738 in yellow gold), I loved its simple bold design. I also really like the Nautilus as well, so maybe I have a thing for these 60's/70's designs (I think Moritz was on to something). I do NOT like the aquanaut at all, which seems to be Patek's answer for a watch for younger people. I am also not into highly complicated timepieces, or large diameter watches, which represent a large number of the watches being marketed to younger people today. I really like simple, clean lines, and of course, immaculate craftsmanship. My Father passed down one of his Patek's to me as a high school graduation gift ( a 5024 Gondolo), which I wear daily. I love the streamlined Art Deco look of the watch. I find I can dress the watch up or down. I also have a Rolex Daytona, but I am not much into large diameter or more complicated watches (as I stated earlier), so this one does not get as much wrist time (it is also quite heavy because it is white gold). So, for me at least, I find the Calatrava to be an attractive model, especially the dial on the 5196, but I prefer the Golden Ellipse and Nautilus over the Calatrava. My friends who are into watches wear Panerai and Rolex, and they feel Pateks are a little bit too conservative, but they also expressed that they liked the Nautilus as well.