Got it in my hands. Crazy, man! The complexity comes from its ability to use waveforms to generate FM modulation of other waveforms, especially over time.
It likes to be a bit sandy, grindy, and dirty, but it doesn't have to be. It can be sweet and well-behaved as well. The SL license gives you the ability to upload your own waveforms into it.
I am reminded of Native Instruments (Reaktor), who similarly lean towards gritty sounding products that you can reign in. Perhaps this is a German synthesizer aesthetic characteristic?
Waldorf also has a sly humor in some of their materials that you could easily miss if you aren't paying close attention. Love it.