Slightly off-topic, perhaps, but I've taken a long-term rail replacement bus from Prague to Nuremburg. It was a DB-liveried double-decker coach. I had a 1st class ticket from Prague to Cologne, but I was extremely surprised to be duly conveyed in the 1st class section of the bus!
In reality, it was a bit daft really, as 2nd class is upstairs, with 2+2 airline seating and 1st class is downstairs with all seats around tables. There is a coffee machine (which the driver demonstrated how to use to me and the one other 1st class passenger!) and a selection of literature in German.
It being the continent, the coach is not particularly high and so the downstairs headroom is only about 5'6", which makes the journey a bit uncomfortable. However, I appreciated the coffee (after a lads' weekend in Prague) and somewhere to spread out my newspaper.
Mark