The actives compete with speakers eight times their price.
Each set of drivers (5 sets total) is driven by its own DSP and amplifier channel. A 660 would require the same number of channels as an 1100. Not much cost saving there.
Actives are for folks who want it LOUD and accurate.You'd want them for parties, if you sit 18 feet away or more or because you want the most accurate presentation at any volume level.
I summarized my thoughts with this review:
The M5s, M100s and active LFR1100s are skillfully-crafted, high fidelity sonic holography engines that carve out a 3D space and sculpt acoustic images within. The active LFR1100s are considerably more refined than the passives and offer greater stage width and depth (right out my bow window), improved image placement precision, higher image spatial and acoustic resolution including more "black space" between the images, improved quantity and quality of bass and mids which must be heard to be believed (they sound better than my passive system with three Axiom sealed subs), improved macro and micro dynamics and an enhanced ability to acoustically disappear particularly with high quality recordings. The active LFR1100s add up to a more emotionally satisfying experience than passives at not only high SPLs but also lower SPLs where passives only start to perform. It really is nearly impossible to go back to traditional speakers after listening to the active omnis. The technical differences between the passives and active omnis are transparently revealed in the frequency response curves on Axiom's product pages. As one moves up the line of products, the listening window and sound power curves extend further across the audible spectrum, are more linear, and closer aligned. The active LFR1100s offer a textbook example of aligned listening window and sound power curves that decline at 3dB per decade and are free of acoustic resonances. Such a speaker response is impossible to realize with the inherent limitations of passive cross-overs used in traditional speakers. Use of digital filters enables bespoke roll-offs to optimize driver integration and linearize mid-band response. Unlike traditional passive speakers, the filters are located upstream of the amplifier resulting in higher speaker sensitivity, improved stability in the response at higher power levels, lower thermal noise and improved control of the drivers. The result of this implementation is a speaker system that "plugs into a room and plays" with no EQ required and effortlessly renders the performance the sound engineer intended. | 
