You cannot compare stock Kenwood HU with aftermarket higher end stuff. Stock HU normally is not top of the line stuff, more like mid range level, hence you'd feel the aftermarket Pioneer is surely better. If you replace with high end Kenwood also it should be better than the stock Kenwood HU from the car.

Traditionally Kenwood has a warmer sound while Pioneer has a sharper digital sound. So for me personally I prefer Kenwood and I also have used both in several different cars. The Kenwood has a 5 Volt output while the Pioneer is 4V, therefore the Kenwood should have a more open sound (if you connect thru power amp) even though both are already classified as high output (normal output is just 2V). Sound quality is also pretty subjective or a personal preference. But that is just sound alone, not sure about features. For features you just have to compare in detail and pick which one has the more suitable features for you.

This post has been edited by 6UE5T: Sep 16 2017, 12:23 PM