Horn based loudspeakers why the controversy?

Well, being an owner of new Klipsch Forte III's, I thought I'd chime in. Had Magnepan .7's for awhile and really liked them. In my listening area I knew I was only getting about 75% of what they could deliver because of space considerations. Took the plunge on the Forte's (my 3rd pair of Klipsch over the years). I can say I am very pleased and frankly, pleasantly surprised. They are the most refined yet dynamic sounding Klipsch I have owned. They aren't for everyone but with my taste in music being primarily electric blues and classic rock (Yes spinning now) they fit the bill. One man's trash, another's treasure. Using a Rogue Sphinx with upgraded tubes with splendid results...

@analogluvr 
How exactly do you figure inefficient speakers can't be dynamic as all hell given robust power? That math doesn't work. Sure, many inefficient speakers are limp on account of torpid power, but there's nothing inherent preventing them from being dynamic. You accuse me of relaying outdated or inaccurate information, but what you're saying hasn't been true since the power wars of the 70's. 
No offense, but you and johnk seem to believe audio hit it's zenith in 1935 or there about and everything since has just been regression. No matter what anybody seeks, you two prescribe massive horn loaded solutions and low power tubes. Prescribe for me the fully horn loaded full range speaker that will fit within 2 or 3 square feet and is suitable for listening at 10 to 12 feet using modest solid state power that costs less that $5000. I think those are very common demands of a great many people here. You guys can't even bring yourselves to admit those speakers don't exist, much less appreciate that's not a practical solution for many. At least HR admitted the 936's came surprisingly close to the dynamics of the Uno Nano's so I know I'm not listening to a couple of compressed piles of junk. You and johnk and a few others talk like there's some vast chasm of difference and that no shortcoming of horns compares to the failings of dynamic drivers. It's frustrating to those who don't agree. And you guys just don't take no for an answer. 

The real irony to me is that the same people who vehemently argue for the dynamics of horns are the same who think vinyl is king. You don't get more dynamically compressed than vinyl. Why the big concern about your speakers dynamics when your source can't utilize the capability?

My first my first encounter with horns were Klipsch La Scalas driven by early transistor amplifiers. Not pleasant—but great party speakers. Ditto classic Klipschorns. Never heard these with any kind of tube amp, let alone an SET. Fast forward 30 some years and I heard a pair of Avant-garde Duos driven by an all-BAT tube system. Astounding! The bass (which is delivered by a conventional powered woofer), was not dialed in at all, but that was not the speaker’s fault. Victor Khomenko, BAT’s designer just hadn’t gotten around to that. He was running a prototype of a new phonostage and he wasn’t listening for the bass. Victor is big on what he calls “dynamic tracking” and horns do that very well. At very low levels, many speakers just don’t respond at all. They operate like a noise gate in a recording studio; everything below a certain threshold is just swallowed up, rather than being reproduced. Horns avoid that problem, although they have others including, sometimes, significant coloration and a lack of low bass (unless they are really large, like a K-Horn).

Kosst- Altec -a7 a5, Klipsch- Lascala Belle Khorn all run well off class A SS all are under 5k pair- fully horn loaded systems get large and thus costly. Also since you only know me from a few posts in this forum you are not aware that I design loudspeakers and many that I have sold are non horn loaded designs. You also seem to form wrong conclusions based on having limited experience with horn based loudspeaker systems so I can understand why you find loudspeaker discussions complicated and frustrating. And I do feel I have the right to suggest horn loaded options in any forum at anytime I dont see why that is such a issue for you?  And why do you insist others agree with you?  Sorry but I haven't read much of what you post and what I have I haven't seen anything to agree with. 

Horns were virtually ignored by the "high-end" journals like TAS and the Stereophile back in the day. The transition to solid state probably didn’t help either, given that a lot of early sound state gear could be rough on the ears. Size mattered too- I had an older friend while I was finishing college who ran a pair of old K-horns with then already vintage Marantz tube gear and it sounded pretty good. (At the time I was using the original Quad ESL and Audio Research tube amp and preamp).
The notion of vintage horns like WE, RCA, JBL, etc. seemed pretty removed from the collective wisdom being preached in the era when I started fooling around with "serious" gear--the very early ’70s. I think it wasn’t promoted, manufactured or sold much in the States for consumer audio, and certainly wasn’t given the imprimatur of the authorities of the day (back when reading Harry Pearson and J.G. Holt was meaningful-i think people are far more skeptical of reviews and reviewers today, which is a different subject).
I know there were hardcore horn enthusiasts in the Far East. And perhaps a few on the fringes here in the States.
What products revived the horn? Avantgarde was certainly one; there are probably some others, of recent manufacture within the last ten years, along with greater awareness of vintage equipment, like idler turntables and SET amps. (My Avantgardes didn’t really sing until I got a pair of Lamm ML2s).
A hybrid horn system is still a challenge--matching woofer characteristics to the mid and high frequency horns. A full horn system including bass horns is not only large but unless you are DIY, costly. (Even DIY is costly if you are using vintage or more modern high end compression drivers).
I know some people that visited me over the years were surprised that there was no "shouty" ear bleeding aspect to the system--part of it was set up, and a lot had to do with associated components. I’m not sure how effectively horns have been demonstrated at hi-fi shows after their modern resurgence (I don’t go to audio shows much any more).
I also don’t listen at crazy high dbs. In fact, I can get a lot of information at low volume levels, but the bass (I supplement with 15 inch servo woofers, not ideal, but cost-effective) doesn’t really come alive until the system is played at "normal" listening levels. I think the dynamic capabilities aren’t just about "peak loudness" but the so-called ’jump factor’- the ability of the system to make those dynamic swings effortlessly. As a decades long Quad listener (still have ’em, just got ’em restored), I’ve always been about the midrange first- open, non-grainy, not "reproduced" sounding. Horns give me that. The Quads are easier to set up but have even greater limitations. I love both.
I’ve heard very convincing conventional coned speakers- such as the Rockports, driven by very substantial amplification and a good analog front end. Such systems do some things better (at least in the bass region, unless you have horn woofers).
It’s all trade-offs somewhere. Pick your preference. I’ve been extremely happy with my horn system for the past 11 years, and know that I could do better if I threw more money at it.
For the last few years, my priority has been obtaining records. The system is sufficiently "good" that I’d rather have more, different, and interesting music to listen to than constantly upgrade gear.