Commentary and sightseeing are often delayed, and the quality of the audio is not particularly good. We also drove in circles several times. But still recommended as a first overview of the city. The river trip was very nice, 5 stars for that.
Easy to spot the buses. Friendly staff. The tour is a recording listened to by headphones which was great if the recording worked all the time but on one bus it kept cutting out. It was hard to keep up with what they were talking about as we kept on driving past the sights, but was interesting to listen to. Good that you can choose the language to listen in. Detailed map given with the stops listed and drivers were good at stopping if you were on your way to a stop when it arrived.
Quite good, I recommend it for your first day in Budapest to see a bit of the whole city and stop where you want but for only 1 day the journey is always the same so for 2 days it's not very useful. The entire walk without stopping is 1h30, you have an audio guide in all languages and a map in paper version. The boat trip was good but too many people on the boat, we weren't able to get on the top of the boat which was a real shame