I just bought one of these drivers and I am ecstatic. I am clearly 5 - 10 yards longer and feel comfortable with the Aldila shaft. I have not seen "pushes" or "fades" that you sometimes see with a longer shaft.
They are both 460cc, so I don't think one is bigger than the other.
I believe there is added weight in the heel to be slightly on the draw bias and the club is designed for slower speeds versus the regular A3. I believe it is supposed to have a higher flight as well.
I don't make this stuff up, this is what Adams and other web sites report.