Aftermarket stereo nav units ... Who makes the best and which ones will work in the mk6 ? I just purchased my first VW , 2012 Golf TDI Highline 6spd man , but no nav . Dealer wants 2400 for a 310 unit . I think I could get a top of the line Kenwood or Pioneer unit plus better speakers & sub for that kind of cash . Any thoughts or helpfull info ??? I'm a VW noob here just looking for info .