For a great Requiem on period instruments (if not exactly period playing
style) try the Harmonia Mundi with Gerhard Schmidt-Gaden conducting the
Toelzer Knabenchor and the Collegium Aureum.  The only deficit is that the
boy soloists (soprano and alto) do not bring to the parts the maturity and
insight that you could expect from grown women, but for the rest this is a
powerful and otherwise outstanding recording.

I've also found Malgoire's worth a gander.

Aaron J. Rabushka
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