i got my 2016 GLE350 a couple of weeks ago.  I got the standard sound system.  I was originally disappointed with the sound system, wishing I had added the upgraded sound system, especially since there was no bass.  I adjusted the bass, mid and treble, and was still disappointed.  Then, I adjust the fade.  I put more volume toward the front, and then there was the bass!  It made a dramatic improvement to the sound.  I'm much happier, but I do wish I had looked into the HK system before buying.  If I was to do it again, I'd definitely listen to a car with HK and compare it to a car with standard before ordering.