fsgattuso - the CS1.5 is a sweetheart!
I’ve been using a pair this summer to run XO and wire experiments, along with mix and master evaluations. Mine are stock form, but have upgraded crossovers in their foreseeable future.
I’ve observed that any of the models with their crossovers remote from the woofer are simply cleaner and clearer. Many models mount the XO behind the woofer (for production ease.) The 1.5 mounts it behind the passive radiator for less electromagnetic interference. Five generations of the model hit the spot. I believe the CS1.5 spent its entire model tenure (1993 to 2002) on Stereophile’s Class A (limited bass) list.
This 5th generation of the model/format shines as a nicely matured loudspeaker - with room to grow using all its basic components.