We are traveling from Budapest to Vienna in August. We have heard that Day Trip is a good option-reasonable cost and time. Has anyone used them? What was your experience? Is the train better choice?
Don't know Day Trip. The train is clean and fast and cheap.
The train takes 2,5 hrs and can be as cheap as € 19. With taking the 7.40 you'll be at Vienna Central (Wien Hauptbahnhof) at 10.20. The metro (U-Bahn) brings you within 10 minutes in the very city centre (Stephansplatz). The last train back is at 19.42.
Here is the MAV link http://elvira.mav-start.hu
I always wait to by tickets for day trips or over night trips as it gives me the option to stay put or leave earlier or later. Trains rairly sell out. You might also think about spending the night and taking an early train back. Cities have a whole different character in the evening.