I thought that the Railjets go pretty fast between Vienna & Salzburg, but rather slow between Salzburg & Munich (I only went on it once). The 2nd class coaches only have lino flooring, the seat backs are too upright/high and they don't recline. No idea about 2nd class. They look good though, epecially from the outside, and appear to have been built like the proverbial brick ****house
The middle section St Poelten-Linz-Wels is the fast bit.
160kph (or less round the many bends) from Wels via Salzburg to Munich.
The new lines around Vienna are supposed to open in December.
Until then it's also 160kph on the winding old line as far as St Poelten.
I did 1st class in July and was not that impressed.
They are nice trains, but the styling is naff.
Some of the window glass is obscured by the slanting outsize "Railjet" logo on the outside.
Much the same OBB stock, in more traditional styling, also runs Vienna-Prague-Berlin and I found that to be nicer.