They can be ordered with HP drivers although that option isn't available on the order page.
The M100 and LFR1100 come with HP drivers.
It would be an over-simplification to say the M100 is like an LFR1100 without rear firing drivers. The M100, as good as it is, still "colors" the sound. The active LFR1100 does not. Bass on the active LFR1100 is more linear, soundstage is wider and deeper and images better defined and more stable. With proper placement, the actives acoustically disappear. I was never able to get the M100s to do that.
