Yes we had a great trip. We cycled the route from Vienna to Budapest usign the book, The Danube Cycleway, as a basic guide. The campgrounds in Hungary were great.
We travled by train between Budapest, Kracow and Prague. The folded tandem, in its carry bag, along with the two pullman-size suitcases that become the trailer made for some awkward luggage but we did fine.
After a few days in Prague we loaded up and rode basically south through the countryside following the main Greenways cycleway (pretty well marked with yellow signs the whole way). Our route included Czesky-Krumlov, Trebon, Telc, before crossing back into Austria and heading for Krems. Our last day on the bike, Krems to Vienna was easy going along the river, compared with the continuous up and down of the previous five or six days - very hilly in CZ.
The bike performed very well. We carried everything we needed for 21 days including light camping gear in the two suitcases stacked. We used the heavy-duty axel as we probably has a gross trailer weight of 80-100 pounds. This is the only tandem I have owned so I can't make comparisons, but the bike is solid and we encountered no problems. Once we get our trip organized we'll post a travelogue and pictures on the web.