Come to think of it, I was just talking about the Pie Jesu of Lloyd Webber on Sunday with Miss Anne...
Here is Hayley Westenra, the New Zealand singer, singing the Pie Jesu at the National Memorial Day Concert in Washington, DC. Sorry, embedding was turned off by request.
Westenra has a beautiful voice. If it weren't quite so booming, I'd have no problems with this at an actual Requiem Mass during Holy Communion. The rest of the music, not so much. But hey! I have to take what I can get!
I believe that Lloyd Webber derived the music for the soloist line of the Agnus Dei from the plainchant. The background from the men's choir is tremendously strong, and very clean. Sometimes men sound quite grainy. It makes me remember that I will die some day.
For comparision, I looked up the Dies Irae from Verdi's Requiem. One of my generation might recognize its opening sequence from the Harry Potter Quidditch World Cup game. No comments on whether I did or not, or Potter generally. The low brass is fantastic; I quite like that about Verdi!