Single driver vs traditional 3 way loudspeakers

Here is the single good full range driver implementation without front horn I have heard.
Tune Audio Marvel
https://youtu.be/JCLuH_NeVgI
They use Fostex FE208EZ without whizzer and tweeter with big horn.
The crossover point between full range driver and tweeter is 2500HZ.

A huge system from Russia - AER driver with big AER transparent horn + 2 x 4 x 15inch bass drivers.
Start listen from 1:12
https://www.youtube.com/watch?v=WF_ZeYVgAf4&t=4913s

Most of full range drivers have incline frequency response. And with a backloaded horn implementation they have a dip in lower midrange that causes dry and bright sound. To compensate it front horn should be added.
A good example is AER big transparent horn.

I don't have experience for adding super tweeters to full range. But with compression driver horns - 4th order crossover works 1000 times better vs 1st order crossover!!! Much less high midrange distortion, sound smoother more detailed, bigger and deeper soundstage, better clarity and separation. You can follow over interpretation more easy and enjoy music. I always used forward firing super tweeter and I did alignment for both 1st and 4rd order crossover implementations.

Correct, i can say most of full range drivers got dip in lower mid ----upper base 150-300 Hz that causes tiny sound .