I fall somewhere in the middle. My wife and I spent a few hours in Siena last week. Honestly, the big campo was not a huge attraction for me, but the Duomo is absolutely incredible and well worth the visit. Because we were in Siena for such short time, I knew there were plenty of things I was missing...things that would have helped me to form a connection with the place. I think if I went back there, and stayed overnight in the city, and if the crowds were a little smaller, I would get a lot more out of it. Whether I would enjoy it as much as San Gimignano or Montepulciano is another matter, but I clearly felt that Siena had a lot to offer, and I hope I can go back someday to explore it in more depth.

I went twice, once by bus from Florence and once on bike on a cycling tour. Each time I entered from a different gate. The bus drops you closer to everything on the tourist hit list and now that I've been again, I felt like we were on the greatest hits tour of Siena. Somehow, the gate we went through on bikes was different and I felt I got a totally different feel of the town. Plus I realized that there's a "real" modern city outside the town walls. I think if you make the effort to stray off the tourist trail a bit, you might be more wowed.

That said, the Siena duomo is my favorite church I've visited. The marble is stunning and the inside is overwhelming to me, plus I love the Piccolomini library.