what’s the most dynamic and detailed driver 4 to 5”?

I find the best balance between dynamics and detail in the Alpair 10.3M. They have the qualities the 7.3 has, but as they are a bit bigger, they are better dealing with the dynamics and are still very detailed. I even own 2 pair of them. One i use as nearfield computer speakers at my desk where i'm now, and even if i'm less than a meter from them, they do sound very good. The other pair is used in waw with a 10" woofer where i sit 3 meters from them and there it also gives the details i want and is it even more dynamic (as it need to give less bass).
 
The evolution of the Alpair 10.3 from the A10.2 was very much abut raising its mid/top qualities very close to what the A7.3 is capable of, but for most the extra cone size, dynamics, and bass overrule that when used FR as opposed to midTweeter.

It does take a serious amount of time to reach its best (500-1000 hrs in our experience)

dave