Isn't this an area where you pretty much have to take what you can get? The Muti recordings of various masses are meant to be the ones to get - I can neither confirm nor deny this having never heard them, but I do have Spering and Das Neue Orchester doing a Requiem in C minor on original instruments, which sounds good to me.
Cherubini is a composer of some originality, and the masses were admired by Beethoven no less, with the C minor one at least being a striking work (I haven't heard the other one sad to say). Muti's versions are meant to be very good - I think the disks are well worth purchasing if you feel the urge to investigate further.
This twofer contains both the Cherubini and Verdi requiems. Both performances are awarded three stars (out of four possible, untypically enough) in the Penguin guide. I have not heard either performance but would say this item seems worth picking up, especially if the price is right and you also have use for a(nother) Verdi requiem.
No, I think both requiems were by Cherubini: C minor and D minor. It's a red thing. I'll go back today maybe, to buy it. It'll probably still be there. I can't seem to find any info on it online, but if Muti's supposed to be good, it'll pay to check it out. I shoulda checked the price...