nav command repair? on 2005 Mercedes-Benz S430

the navigational/radio quit working and it is definitely the in-dash unit. who repairs these besides MB?

Asked by for the 2005 Mercedes-Benz S430
Google "original stereo equipment stereo repair Sacramento Ca" I found a lot of places that repair OE stereos. For stereo removal look at or Alldata is very easy to navigate
well, i'm sending the unit off to:
Radio Medics Services
3301 Sunrise Blvd. Suite K
Rancho Cordova, CA 95742
(916) 851-9261

they've said about $250 to $500 depending on the problem. has anyone heard of this company?