This was a great challenge. The Danube Bike Trail is magnificent - it's something that everyone who enjoys biking should do at least once in thier lives. And parts of it they should do more than once. This tour was perfect for obtaining an understanding of the trail. When I do it again, I'll bike fewer kilometers per day in order to have more time and energy to visit the beautiful and fascinating places along the way.
The support provided by the local company was good. Suitcase delivery was dependable. When, two days into my trip, I realized that it would be better to have an e-bike, they delivered one to me that very day. (Unless you are in very good shape and know exactly what you are doing, I highly recommend you go for an e-bike).
I preferred the trail from Passau to Bratislava. After Bratislava the trail changes - it is not as well sign-posted (it's especially poor in Hungary), and the surfaces at times are challenging (several gravel roads, unpaved paths, and at one point you follow a dirt path in between train tacks and an agricultural field without a single sign post to be found). Also after Bratislava siginificant portions of the path are so far from the river you cannot see it, which makes the lack of sign posting a bigger problem. Arriving in Budapest was a shock to my system - after two weeks of peaceful countryside, I wasn't ready for the hustle, bustle and noise of the city.
I don't recommend getting the meals package. I did and regretted it. While some of the restaurants offered excellent meals as well as excellent service, most did not. Most of the restaurants offered me highly limited choices of mostly bland, uninteresting food and resentful service, I guess because I was paying less than the customers ordering a la carte? Whatever their reasons were, they definitely made me feel like a second-class customer. I would have been happy to pay more for more interesting food and kinder service.
My biggest critique is that it was impossible to reach anyone at Biketours.com by phone. Covid or not, I strongly fault them for this - it's not right to sell complex and costly tours like this without being willing to speak with your customers. It would have been extremely helpful for me to be able to speak with someone knowledgeable at least once while planning my trip to be sure I was making the right choices for me.
I did this tour as a woman in my mid-50s, traveling alone. I never felt unsafe. If I can do this tour, anyone who can ride a bike can do it. But I do recommend an e-bike.