As you say, the dynamics are great like many large semi horn loaded speakers (Tannoys, Klipsch etc). Where, for me, the JBL's differ from speakers I had before such as ATC, Focal and Proac to name just a few, is that that use a huge 15" paper cone to produce the fundamentals of virtually all instruments. This gives a gravitas and a "chewiness" to percussion, bass and the lower reaches of many instruments that I hear live but rarely through hifi systems.
These are basically a huge two way so they are also really coherent. I've heard monitors that image better if that's your thing but I'm more of a "tone" man.