We had previously taken the Rhine river cruise a few years ago, and enjoyed it so much we decided to take the Danube cruise.
First our cruise director Tony is wonderful, most thoughtful and innovative. Handled difficult situations with ease. Would take another with him any time.
One downside, compared to our previous cruise there sere quite a few "extra" (non included) day trips which we interpreted as just extra money raisers. There were some days that if we hadn't taken an extra cost activity there was no activity. This raised the total cost to quite expensive.
The term "balcony" is a misnomer, as there isn't really one. And were were advised to not open our sliding door at night as flies would invade. The evening happy hour and entertainment were fine, Drinks other than Happy Hour were expensive. The wine furnished with dinner was of local variety, and most were somewhat dryer than we like. The wines on the Rhine cruise were much better. During the cruise a part broke in the ships steering and the captain handled it as though nothing happened, the director rescheduled the next mornings tours to leave from a different location but return us to the originally designated location. I'm sure that took some juggling!
I was a little disappointed that the daily on land tours were fewer "included", and many more "at extra cost" were available.
All in all, I would take the Rhine cruise again before the Danube cruise.