the voice control whilst far from perfect is certainly better than it was in the MK5 Golf or the Scirocco with the RNS-510. Don't know if that was down to the head unit itself or the placement (quality) of the overhead mic, but it was bloody frustrating non the less.
When I was driving and I wanted to say change the album playing on the SD card or Ipod, I would hit the voice button, wait for the bong then say "SELECTION" (so far so good), then the current album playing would be displayed on screen with a number against all the tracks. If I wanted to come out of this album and go up a level (say for instance I was listening to a specific Queen Album then wanted to come out of this one to see all of the albums by Queen), I would say the command "UP", and it was supposed to take me up a level, however try as I might, it would always respond with "MAP", then take me to the navigation screen. I tried saying the work softly, loudly, with an accent, holding my head up near the mic, but it would only work (sometimes) if the car was at standstill with no road noise. Frustrating to say the least, and the same for a lot of other commands.
At least in the GTD it recognises the commands about 90-95% of the time correctly and allows me to enter an address for navigation, browse the music collection, dial a number etc. The only problem is that it's a bit clunky, not very quick and you have to speak the commands correctly. Perhaps in the next generation of voice control VW will crack this ?