I took the Berlin-Vienna NightJet last spring, and enjoyed it myself. It's a typical sleeper train experience (some people like them, others don't, but it's worth trying one once to see which group you're in).

The rolling stock I was on was relatively new, clean, and in good repair. I didn't have the in-compartment shower, but still had a private washbasin and electrical outlets. There was a shower at the end of the car that was perfectly fine.

There was no dining car, but I was pleasantly surprised to find that there was a (limited) dining menu available on-board (you eat it in your compartment). I didn't try it myself, because I'd already eaten before boarding, but it looked OK (and the prices were reasonable). The included breakfast was quite respectable.