This is a tough call; I have owned several convertibles before and loved them; I hate to turn on the AC, instead I have always opened the roof in the summer.
Therefore, I got the Pano roof on my Model S, but am not totally in love with it:
I think the car looks odd with the Pano open due to the cloth wind deflector sticking out significantly. Even with this deflector, you cannot open the roof more than 75% while driving >40 mph due to the wind buffeting hurting your ears. I open the rear windows to let the air escape, but that's not ideal.
I had my windows tinted and now I really sense a lot of heat coming in through the Pano roof, so I may have to get that covered too, as others have pointed out.
In summary, while there wasn't even a question whether I should get the Pano roof for my Model S or not because I was a big convertible guy, I enjoy it much less than I thought I would. The good news is, it has not leaked.