This was our third trip to Europe and the two previous were land based. We were a little concerned about having only limited time to explore the places we visited but this was more than balanced out by the comfort and quality of the cruise ship. The stateroom was small as expected but the bathroom was very serviceable and the bed was comfortable. The room had a surprising amount of storage available.
The ships staff was extremely friendly and seemed to anticipate your needs very well. One time I was lounging on the upper deck and thought to myself that my legs were a little cold. Almost at the same time, someone was there with a deck blanket. The food at every meal was excellent, with a good variety of items on the menu.
Even with the limited amount of time on shore compared to staying in a hotel, we saw quite a bit and almost all the tour-guides did a good job of showing all the highlights they could and many times quite a bit more details than expected.
We had only two complaints. The "Rhine Getaway" tour that we took in April 2015 seemed to be a hectic, constantly on the move, especially the Basil departure and Heidelberg/Rudeshime day. We have read that Viking has altered the tour slightly to try and correct this, such as adding some time in Basil. When we travel with Viking again, we will opt for a longer cruise. The second issue is that atmosphere of the ship regarding the other passengers felt a little stodgy and conservative, like an upscale Midwestern hotel in the US.