Thank you very much for the kind words. It's greatly appreciated. To answer your question, yes, the model I reviewed is pulse width modulated.
Curious what modes you found PWM on. AFAIK, all Quarks are current regulated for all their constant on modes (don't know about the disco modes though). I have the 2L burst mode head and just did time exposure sweeps across a camera for all the loose bezel modes and L, M and H all look completely smooth like the center beam here (L2R @ ~3 lms - MDC AA, QPA-X, Mini MA):
However, on moonlight, there is some "warble" (as discussed in the PWM sticky) on my sample. Somewhat rare among my Quarks, but most are low voltage XML heads.