+1 and good post. That's just the way I view it... a voicing that some will like and others won't... a nice additional choice to more traditional cabs that some will really dig, and the improved dispersion in the upper mids and lower treble below the tweeter is definitely a bonus. No argument there! I surely notice this impact with Duke's cab, and also listening to all the LDS executions I've played in various rooms and on and off axis (although it surely isn't 'night and day' versus my 212 cabs IMO and IME).
Nice that Avatar has an amazingly priced, immediately available version of this type of design in their product portfolio. And that introductory deal is just stupid good... my gosh. I don't particularly dig the 'evangalism' of this design as being the one and only way to get a good even tone out in the room, but it surely is a valid way to get there if the tone profile of the box meets the other requirements that a player might have regarding tone, volume, low end response, etc., etc.
We've discussed this before and I agree that a dedicated mid isn't the only way to go. There are many other valid executions of design that deliver mids/upper mids and to some the sound is preferable without a dedicated mid driver. But it really depends on just how full range the woofer is in the first place. There are many that utilize a good full range woofer and combine it with a good tweeter. But there are also many that don't use very good full range woofers and also use very cheap tweeters leaving that hole in there where those mids are missing no matter how much EQ'ing one does.
Any speaker that does the lows VERY well, will not be a great full range woofer. So once a cab is built with a speaker that does the lows very well and uses no mid driver, but only a tweeter, that's where the mids suffer. That isn't really a preference, but just poor execution and/or design.
So long as companies don't try to cheap out, there are viable alternative designs that give those mids very well without a dedicated mid...and then it's just a matter of tonal preference as to whether one likes a more flat response or one that accentuates certain frequencies more.

