OMG...... you are going to love it. I just got mine a week or so ago, and how else can I describe it except it's almost magical... {sigh}Truly the most comfortable saddle ever invented, and I've tried about a thousand dollars worth - including many you mentioned and the Brooks Imperial models.
If you have *ANY* irritation or pressure points with the saddle send Tom at Selle Anatomica a brief email explaining where and he can tell you exactly how to get rid of them. It took only 2 rides to get mine dialed in correctly with his suggestions.
Happy comfortable riding!
SpinSpinSugar
Edit: Stretching.. mine has barely started to make sitbone dents after 100 miles or so. Maybe it has stretched a microscopic amount. But I have the tensioning bolt almost all the way in - it's nearly all the way loose. According to the directions - you loosen it to make a wider sitbone area, and tension it to make it narrower. I would be a Specialized size 155, and I fit quite comfortably on the Anatomica. At this rate of stretch, I have YEARS worth of tensioning left in the bolt.. oh, and fwiw.. I weigh 140lbs.