...barely two days ago, and didn't have so much time to listen yet;
but it is apparent that this "Klipsch K55v upgrade" is what it is: improving on the "good old" Atlas driver with greater bandwith, smoother response, less distortion while being a completely plug-n-play solution for Klipsch users (or people like me who use home-made frankenstein speakers based on the Klipsch Heritage products).
Mids are very noticeably clearer, more open, less blurry/hazy, and much more natural sounding. In my system they are loaded by EV SM120A horns. 400Hz>6KHz 6dB/oct.
It keeps improving as they are burning in so I expect even better results after another day of listening.
I am of course not affliated with John Allen or with B&K sound, just sharing my experience with a driver that may offer an interesting (and relatively cheap) option for DIY enthousiasts as well.
Edits: 05/29/17This post is made possible by the generous support of people like you and our sponsors:
Topic - Got my John Allen A55G drivers - KanedaK 03:02:28 05/29/17 (2)