I just finished up testing the ScanSpeak D3004/602000 Tweeter. This is the second test I've done on this tweeter, and the explanation is given in the review.
Review can be found here:
http://medleysmusings.com/d3004602000/
Read through the bottom for some cool comparison testing between this tweeter and the Gladen 28mm tweeter.
PS: If you would like to help me keep up funds for testing additional drivers, there’s a little ‘contribute’ button that goes through Paypal all the way at the bottom of every page. Any little bit helps.