Lexicon is a brand of Harman. The premium 15-speaker system in the
Genesis G70 is branded Lexicon, but it's most likely exactly the same as the Harman system in the Stinger. As soon as you get in a
G70, you'll see just how similar the two cars are. They share 100% the same systems throughout, down to the placement of the speakers, so it's not about comparing the branding on the audio system. You will find all sorts of different configurations of Harman audio systems in all sorts of cars. For example, Mercedes offers a basic audio system, a Harman premium system, and also a Burmester extra premium system. Ultimately, branding should never be an indication of whether a particular audio system in a car will be to your liking.
The good thing is that the sound settings in the Stinger/
G70 has some limited tuning options that let you fine tune the sound. Used sparingly, you can effectively tame frequencies at the high and low ends, which is most likely where people that care about audio typically find issue. To me, it's most important for an audio system to be able to achieve a "normal" sound. By this I mean it can achieve a sound that works well with small-band studio recordings. Music like this typically doesn't have much sound stage, so you don't lose out on much when you play it on a speaker system that cannot replicate the sound stage (like a car audio system). I find that not all audio systems can achieve this. There are many audio systems that sound special and different, but never normal. Those are systems that you can have fun with, but you will quickly tire of them because they cannot work in day-to-day listening applications. The Stinger/
G70 Harman system is the former. If you have issues with sub-bass or treble glare, you can roll those ends off with the tuning control. I had to dial the treble back because it quite glaring at the 0 position, and I'm not a person with sensitivity to high frequencies in general. I suspect the glare in the Harman system is due to a local spike in some frequency range that makes it both particularly annoying and useless in terms of adding detail. Putting -2 on the treble was an effective remedy.