Shanghai day-trip: Nanxun or Zhujiajiao?

I'll be in Shanghai beginning of September and would like to visit one of the water towns around. Sadly I'll only have one day to do so... I've decided that it should either be Zhujiajiao or NX. The latter seemingly being one of the most beautiful and least crowded ones, the former being very easily reachable. My question(s):
so is it really just one hour to NX by bus from Shanghai? Considering the Huzhu express line to (much nearer) Zhujiajiao takes an hour too. And are there also buses to NaX as convenient and as regular as there are to Zhujiajiao (maybe one leaving from around People's square)? And quite simply: could someone give me a recommendation wheter the additional value of NX matches its additional expenses?

I thank you in advance!