I'm a low volume listener and one of the things I like about Klipsch is they have that high-efficiency good at low levels thing (as do Harbeth). They are odd things in some respects and certainly have quirks (e.g. no one should ever consider they have heard Klipsch if the amp used was solid state), but they have certainly taught me the 'thing' that horns can do and nothing else does. When I owned Harbeth Compact 7ES and Klipsch Heresys the comparison was fascinating as they each did things right the other got wrong. All speakers are compromises.
FWIW I think there is a staggeringly good speaker in the La Scalas somewhere trying to get out; every now and again they floor me with a level of clarity, dynamic integrity and believability I've not heard from anything else, then I'll stick something else on that makes them sound remarkably odd and coloured (some of this is down to a compromised installation, they are in a second system with less than the best source and amplification). The bizarre thing is it is acoustic music they get the most right - I grew up in a house with a grand piano and the La Scalas are one of exceptionally few speakers that, given a great recording, can get that 'thing' that makes a piano sound like an actual piano rather than a hi-fi playing a piano or a digital sampling keyboard or whatever. I'm convinced it is a combination of real dynamic freedom and efficiency and a mid horn that covers such a huge range (400Hz to 6Khz). The little Heresys were surprisingly good at this too.
They do that 'thing' that single-driver speakers such as Lowthers can do and no two way speaker can. It's a note-shape/envelope/freedom thing. Not many three-way speakers can do it either. With La Scalas it does come at a price though; the horn-loaded bass though lightening fast and articulate is very limited in extension (drops like a stone at 50Hz) and there is an annoying cabinet resonance from, I tnink, the bass-horn walls. Klipsch designs are brilliant IMHO but seem spoilt by more than a bit of penny-pinching. Some cabinet bracing here and there and I suspect the La Scala would be truly exceptional. Ive already got fancy third-party crossovers in mine (ALK Universals). If cost were no object I would unquestionably have huge no-compromise horn speakers. That much I do know. My project for this year is to try and get rather more out of my La Scalas. I've got a little Decware SET on the way - frightening to think that 2.3 Watts equates to about 111db headroom.
