what is the best super speaker and why?

Albert, your mistaken. Call Brian Kurt, Sound Mind Audio..Austin Texas, there sitting in his home/showroom/ living room, just as big as life; if your interested he is apparently looking to move them at a very reasonable price. Roger West at Sound Lab is the one who put me on to Brian Kurt. As for the quality of the electronics driving them, that is a topic that is open to a whole other discussion that is at best subjective.
I have heard that the Avantgarde's can sound really bad if improperly setup..so I have no doubt as to the validity of your prior experience with them. I have heard them only once at Ne Plus Ultra..also in Austin. I guess I was just lucky enough to hear them properly setup.
To change the topic slightly, several of my recent listening experiences have been in home-based dealerships. I feel that this is by and far a better way to hear a system...as opposed to some of the near anechoic chambers or otherwise drastically altered sonic environments I have heard in several dealerships. In other words. if it can sound good in a living room, with minimal sonic treatments..it can sound good in my house..all other factors being somewhat equal. I have both bought and not bought in the past based upon dealership listening sessions, and have often been disappointed with purchases and likely lost out on good opportunities as well.

I took your advice and telephoned Sound Mind in Austin. What you heard are the (old) gold finish Soundlab U-3, not the U-1. There is no comparison between the two.

I hope you find what you are looking for.

It's possible that I was mistaken. I thought Brian Kurt indicated that they were the U-1 design, as he seemed to be describing all other models as being a step down from what I was listening to; if that is the case, I will need to make a point of hearing the U-1. But this just further confirms my point, as I was actually comparing a model U-3 with an Uno; which for my tastes and the circumstances under which I heard them were clearly better...no brightness or hardness at all; and both, I am assuming, around the same price point.
I am curious, as you seem to be well versed on Soundlab's line. The Sound lab website makes no mention of any model U-3; rather U-1, A-1, A-3, M-1, M-2 and M-3. Is the U-3 a discontinued model, like the A-2??? or is it an upgraded
A-2 or M-2?

The Soundlab U-3 is discontinued. If you want this size speaker, the new M-3 is better.

Sound Mind's web site lists these as new U-3, gold finish, and on sale for $12,888.00. The U-1 retails for $32,000.00, making the lowest dealer cost near 20K. I cannot imagine a dealer selling new stock at a $7,000.00 loss. That is why I doubted they were U-1's, but I guess anything is possible.

If you are ever in the DFW area, your welcome to listen to my U-1 Soundlabs.

I would like that, I am frequently in the DFW area on business and often just for pleasure. What would be the best way to contact you to arrange this when I am ready?