Choral or Classical Vocal Recordings - Must Have

In the last six year I have opened my ears to choral music and classical vocal recordings. I would appreciate hearing what your Must Have list is, so that I can discover more wonderful music that maybe I haven't yet heard.

My list is in random order and is as follows:

-Magnificat by John Rutter - COLCD 114
-Lux Aeterna by Morten Lauridsen, Los Angeles Master Chorale - RCM 19705
-Let Your Voice Be Heard - Cantus - CTS 1201
-Olde English Madrigals and Folk Songs at Ely Catedral, Rutter and the Cambridge Singers - AG500-2
-Vepres by Rachmaninov - The Choral Arts Society of Washington - ERATO 2292-45269-2
-La Belle Epoque, The Songs of Reynaldo Hahn - Susan Graham - Sony SK60168
-O Magnum Mysterium by Morten Lauridsen - Nordic Chamber Choir - BR 100 305 CD
-Requiem by Faure - John Rutter and the Cambridge Singers - COLCD 109
-Renee Fleming - Renee Fleming - DECCA 289467049-2
-Litany, Arvo Part - The Hilliard Ensemble - ECM 1592
-Vivaldi Gloria - Robert Shaw Chorus (Dawn Upshaw in this) -Telarc CD-80194
Gloria by John Rutter - The Cambridge Singers - COLCD 100

I could list others but this is the core of my collection which I never tire of. What's yours?