Arnettepartners-
my fave and reference speaker is the Thiel CS 2.4 or CS 2.7 models. This company still uses a passive radiator in all of its glory. For their particular designs, it works very well. Bass response and frequency range is simply, outstanding. For those whom have a listening space like, 20x20, 25x25 or 30x30...the CS 3.7 is a no-brainer.
Find a local dealer/retailer near you and get yourself a demo. It will perhaps change your view on the Passive radiator. Keep me posted & Happy listening.