We are currently planning a two week trip from Berlin to Budapest via Prague and Vienna. Does anybody have any suggestions regarding taking the train versus renting a car and driving. Is two weeks enough time or should we plan for an additional city or two?
I have been to all of the above cities, and have only taken the train between them. I would never consider driving, mostly because I travel solo and train travel in Europe is so simple a child could do it. All of the cities you mentioned have excellent (Berlin & Vienna) to well-above average (Prague and Budapest) train stations and local transit. Tickets are relatively cheap and easy to purchase without reservations. Two weeks for those cities should be enough, however the train ride from Prague to Vienna is rather long and it will take up an entire day. The only other city I would possibly add is Dresden, in between Berlin and Prague. It is well worth at least an afternoon visit, if not an overnight one.
Enjoy your trip.
Train from Prague to Vienna does not take the entire day. It takes 4 hours 40 minutes so there is still some time of a day left.