Concert to MMI Retrofit

Has anybody gone from concert to MMI 3G High? My 2010 S5 was a great example and pretty well specced from factory bar the lack of factory nav.

I know HazzyDayz do retrofitting. Can this work be done within a day or is it likely to run into a couple of days?

I know they do the 3G DVD MMI but from what I’ve read the 3G+ offers much better nav interface?