I had the Dynaudio system in my mk6 Golf, and I must say I was a little disappointed. I found it was good if you like heavy base music, and you have the volume at ‘ear bleeding’ levels, but for me - I don’t enjoy heavy base, and I listen to music at ‘normal’ volume levels. I didn’t find it offered that much over the standard set up. I don’t have Dynaudio currently (I’m currently driving a Polo GTI and it wasn’t an option in the Polo) and I don’t miss it.
The Dynaudio system fitted to the mk7 Golf is meant to be better than the previous version in the mk6 Golf. Judging by the comments on one of the Golf forums of mk7 Golf owners with the Dynaudio system, most would spec it again. Some say that unless you’re a complete audiophile, the standard media system is fine.
I’d recommend going back to the dealer you’ve ordered your Golf R from and ask for back to back test drives in two mk7 Golfs; one with the Dynaudio system and one without so you can do a ‘real world’ direct comparison and judge for yourself. If you’ve not got a confirmed build date for your new Golf R yet, you could always change the build spec of your car to include the Dynaudio option.