What I find most exciting about the set are the spherical, floating sounds that are possible. The Vox Celeste on the III (SW II) is a string but the Unda Maris on the II (SWI) is not so stringy. Due to that it blends very well with all the different flues.
In this upload I used both (Vox Celeste and Unda Maris) in the first section. Imagine the dark sky over Bethlehem is opening and the angel is bringing "News of great joy". Then all the other angels appear and are singing "Gloria in Excelsis deo".
0:00 I. Hear the news the angels bring 1:22 II. News of great joy 2:17 III. Angels and men with joy may sing 3:48 IV. All out of darkness we have light