I have a good 15 or so ocean cruises under my belt, but this was my first river cruise, and my first time cruising solo. The itinerary was Budapest to Nuremburg, with stops in Vienna, Melk, Passau and Regensburg. I did not take the optional 2-night pre-stay in Budapest and 3-night post-stay in Prague, but did arrive one day prior to Budapest and used Ama's air/transfer/hotel package. My driver was waiting for me after baggage claim and I was as the hotel shortly (Sofitel Chain Bridge). When I woke up from a jet-lag nap, there was an information packet tucked under my door, with instructions for meeting up for the drive to the ship the next morning. Next morning (departure day), I had breakfast in the hotel (included buffet) and went out for a walk - glad that I had packed warm! Waterproof boots were a lifesaver! Managed to get a decent picture of the Parliament building in spite of the fog. Then met the bus in the hotel lobby and headed to the ship.
Buses deposited us at the ship and we were directed into the lounge to wait for cabins to be ready (by 3 pm). But we also had the chance to take the bus back into town to visit a Christmas Market or walk around, rather than waiting in the lounge. Check-in was more like a hotel than an ocean cruise - just show your passport at the front desk and get your room key. Very casual. All-aboard was 5:30, after which the ship moved to another dock in Budapest. Several people had missed the boarding due to flight delays, and I heard later from a few that the transfers to finally get to the ship were less than efficient (transfer drivers didn't have up-to-date information, etc.).
I booked this category because it had no single supplement, and was not disappointed. It was small (the bed took up nearly the whole room) but I was not in there much, just to shower, dress and sleep. Flat screen TV had plenty of movie and music options, there was plenty of storage space, and a well-laid-out bathroom with a decent sized shower. There was a tablet on the wall for light and temperature control. The bed was very comfortable.