I will be doing a day trip to Mainz and Wiesbaden from Frankfurt. I am considering the sensible sequence to do it, either Mainz first or Wiesbaden first. Any opinion? It means I will be having my lunch at one place and dinner at the other city. Can you recommend a nice and cheap place to eat in Mainz? How about night view/activity in Mainz? Any suggestion is most welcome. Thanks a lot!