I just installed the Advent OGM1 Navigation unit in my 2013 Silverado. I is definitely a HUGE upgrade from the stock non-Nav head unit than GM uses.

I cannot believe how MUCH better the audio quality is than over the stock head unit.

Installation went pretty well, the most difficult thing was getting the media link installed in the console. The plastic trim around the radio is a real PITA to take off as well.

Once I got the unit configured it is not too difficult to use. I still have quite a bit to learn on the navigation portion.

All in all a real nice unit that seems to just work well with the rest of the truck.