I stayed at the Hilton Mainz this past weekend. I have to admit that it wasn't that bad. Yes it is older, however I found it to be in a nice location. The river view from my room and from the restaurant made up for any faults.
I arrived at the hotel around 12pm, and check-in was quite fast as they had everything ready for me.
As soon as I got to the room I laid down to take a quick nap(big mistake). An hour later one of the staff members knocked on the door to bring me a fruit plate ^. In my sleepy grogginess I turned down the two bottles she had in her hand thinking they were alcoholic beverages. I later found out it was just water.
On my next trip I will hop between both Mainz properties so I will gain more points and miles.