Update after about 20 hours of running in…
The overall character of the speakers hasn’t changed significantly (good, as I still really like them!).
The lowest level HF details are now quite a lot better preserved than with the old tweeters, it’s also easier to hear lyrics clearly - particularly in female vocals. Even more noticeable though, is how much better ‘organised’ the sound is: backing vocals and subtle instrumentation just seem to fit into the soundscape as a whole so much better than before.
On the other hand if I’d not previously improved the crossovers (better wiring and particularly the Mundorf Supreme MKP capacitors), we don’t think we’d have been able to hear the improvements anything like as clearly as we do now.