Aperion Audio Super Tweeter

FWIW -- There was some of chatter about these and the topic in general fairly recently @ AK:
http://audiokarma.org/forums/index.php?threads/thoughts-on-super-tweeters.842925/

I haven't heard 'em -- what I'd recommend is to think about what "problem" you're trying to "solve" before investing too much lucre in the solution

Do you want extension of HF response, increased HF dispersion or a change in the character of the treble? Or all three?

Again FWIW -- I am a pretty dedicated "super" tweeter user due to the limitations of the treble horns in my big-boy loudspeakers. I need extension (but not into the ultrasonic!) and dispersion. The "supertweeters" I use aren't technically supertweeters, but they mate fairly well with the treble horns using a simple first order XO and an L-pad (variable) to normalize the output.

Oh it will make a difference. It looks like you can shape it to some degree with the
AAST. As Doc stated so well, will you be able tune it in to your liking?
I would save the money for speakers that have been designed for use with
a super tweeter. FWIW.

well, I would say "save your money and experiment with something a little less dear (as in
less expensive)"

I wouldn't discourage anyone from playing around a bit. That's how we learn -- unless, of course, we manage to kill ourselves in the process. In that latter case, we do still learn, but it's fairly academic at that point.