I've been playing around with these for a few years now and love them. They are a very vesatile and easily implemented midrange. The high frequency extension is well enough to use with a tweeter (given a proper application), but they really open up a variety of tweeter options with your ability to pretty much HP your tweeters wherever you want.
Best setup so far was a 3-way with Midbass up to 400, Auras from there till 6500, and the tweets handling the rest. Worked great for me.
Oh, and Madisound is still selling them and actually a newer version was/is supposed to be available as an improvement was deemed necessary for wire connection purposes.