Thought I would follow-up with my thoughts from my trip:
Note - for most of these tours, you can make your choice the night before / the day of / really any time before the tour starts. The only exception to this are the Bike Tours, which you have to arrange with the Cruise Manager once on board. The “Special Interest Tours” like Apricots & Sweets and Tastes of Slovakia are also capacity restricted, but I didn’t get the impression that either of them were full or pressed for available slots.
Budapest - Castle Hill Hike or Queen of the Danube Tour
This tour had the best guide of the trip. Our guide Szilvia was extremely knowledgable, hilarious, and managed to keep us entertained non-stop for the entire tour. If you spend any amount of time in Budapest prior to the trip and can do the Pest side on your own, I would highly recommend the Castle Hill Hike as it’s a phenomenal way to see the Buda side of the city. We finished by walking across the bridge and learning a bit about the Parliament Building. We then headed back to the boat on the tram with our guide. Clocked in at just over 5 miles total of walking. The elevation gain wasn’t really much at all - especially compared to some of the other Castle Hikes on this trip.
Bratislava - Coronation City Walking Tour or Tastes of Slovakia or Bratislava Castle Hike
This was the only tour of the trip where we did not have a very good guide. This may have been because we had ~30 people on the Castle Hill Hike (far higher than what is typical from what I could tell) so they split the Castle Hike in Bratislava into two groups. We did bring up our guide experience to the Cruise Manager and he said that others had also mentioned this, and that he was going to make sure they never use that guide again. That being said, the castle itself is not *that* particularly interesting in my opinion. However, the views across the river to the other side of the city and the border with Austria are quite nice. Given the short amount of time in Bratislava I may have been better off just exploring the city on my own.
Vienna - Imperial Vienna Tour or Vienna Bike Tour
The bike tour was as a great way to see the city - we started at the boat and worked our way to the city center to the major sights. Due to the stops for traffic lights and the fact that we had a 30 minute free time period in the middle of the tour, it wasn’t overly strenuous. I was extra glad we did the bike tour since you have to take a bus to Schonbrunn Palace and I would have had serious bus fatigue if I had done the Imperial Vienna Tour in the morning, which features a good amount of bus rides.
We didn’t do the Mozart concert - but the people who went seemed to enjoy it. It’s only about 60-90 minutes of concert time, so not overly long.
Krems - Durnstein Walking Tour or Durnstein Fortress Hike or Krems Bike Tour or Apricots and Sweets
Half of my group did the walking tour and the other half did the Bike Tour. The walking tour was nice, and Durnstein is a cute town (although I get the impression that it can easily become jammed with tourists). The half of my group that did the Bike Tour raved about it - this is a great place for cycling as the Wachau Valley is extremely scenic and you get to bike through vineyards and other lovely scenery. Was thankful for the warning from others on the Fortress Hike - getting up to the Fortress looked intense.
Spitz - Melk Abbey Visit or Spitz Hike or Spitz Bike Tour
It’s a relatively short bus ride to Melk Abbey, where you pick up an Abbey-provided guide to tour the inside of the Abbey. This tour was a bit of a letdown in my opinion. While our guides were excellent, most of the Abbey tour was spent in the “museum” portion which was not particularly unique or interesting, and a short amount of time spent in the libraries + church which are the real highlights and reasons for visiting. While the church interior is great, I wouldn’t call this a “must do” attraction if you feel like taking the afternoon off / exploring Spitz etc.
Linz - “UNESCO City of Media Arts” Walking Tour, “Cultural Mile” Bike Tour, Full-day Salzburg, Full-day Cesky Krumlov
As expected, the Salzburg option was the most popular excursion. Salzburg is pretty and you get a good (2+ hours) of free time to explore the city, but man the Salzburg core is packed with people. This is also a LONG amount of time on the bus. About 1 hr 30 min on the way there - but you stop at Mondsee so it doesn’t feel as long. Wished I had more time to explore Mondsee as it was very scenic and far less crowded than Salzburg. Leaving the city it took us about 1 hr 45 to get back to the boat. Overall, probably worth doing if this is your only time to see Salzburg but the time on the bus was significant. Salzburg or Cesky Krumlov are really your best options (other than taking a day off perhaps) as Linz is not really a tourist city as others have said.
Passau - “City of Three Rivers” Walking Tour or Passau Castle Hike or River Inn Bike Tour
I think at this point in the trip, most of the people on the boat had “lollipop burnout” (the lollipops are the signs held by the tour guides while leading tours). We only had 9 people on this hike. Our guide Guido was lovely. We took a route that involved climbing a lot of stairs in a (very pretty) nature park before reaching the Castle, which provided terrific views of the city and offered us the ability to see the different colors of the three rivers that meet in Passau. Finished by briefly walking through the city and seeing water level markers on the buildings. Overall this tour definitely exceeded my expectations.
The “Spitz Exclusive Wine Event” and “Oktoberfest Celebration” were similar in that they were both cheesy and I would argue pretty weak.