My husband and I recently travelled from Budapest. We explored Budapest on our own and joined the ship under our own steam. We spent an hour trying to find the boat, which was not where they explained it would be, and we were lucky to have a patient taxi driver who did endless u-turns and asked many questions of the locals to finally find it.
Travel Marvel is at the cheaper end of the market, so you get less of the items you might not want less of. It is also clear their boats get the least central berths in major towns.
For the cheaper amount you get very average food, less communal space, and cheap deckchairs on top with no waiter service. The roof-top as a space is also very limited, since it is shut down for days at a time, because of low bridges (this may not be limited to Travel Marvel boats, but should be remembered if you like to get out of the confined space of a river boat). The saving grace was our French Balcony cabin which was very comfortable with lots of places to stow your gear. We were most disappointed in the food and the dining room. They squashed us in and the air conditioning strained to provide the coolness we all craved. The food was poorly cooked, a lack of fresh vegetables (very little green) and the fruit lacked variety, mostly melons of varying colours. One day we had fresh strawberries. The German fields were full of ripe strawberries - but we only had them once. The soups tasted like reconstituted Oxo cubes with rehydrated bits of vegetable. The ubiquitous roast chicken (always the fall back position on the menu), came with oversalted gravy. Wines served with meals, were low-end and unvarying, the white mostly a chardonnay, and the red nearly always German (neither of which were good tasting wines). The staff were extremely hard-working, always smiling and very polite, but most had little English, so it was a struggle to be understood, especially noticeable in the dining room when you wanted information on the food or wine. Finally, the evening's entertainment was held in the one Lounge Area which also contained the bar. If you didn't like the entertainment, and the roof deck was shut down, there was nowhere to sit with friends for conversation and/or after-dinner coffee/drinks, other than a few chairs in reception.
Good cabin facilities. Bed comfortable and bed linen right for the climate. Plenty of cupboard and wardrobe space to empty your suitcases. Could open wide the french door for fresh air, unless another boat docked right beside, when you needed to close door for security, and curtains for privacy. This happened quite a few times.