OK ... these two discs are not directly comparable - the Ciofi/Didonato is a collection of duets; the Mingardo/Piau is a mix of duets and solo arias. But, that said, they have in common the duets 'Caro amico amplesso' from Poro and 'Scherzano sul tuo volto' from Rinaldo, so it's very interesting just switching between these to see how they compare.
I must say at the outset that the Didonato/Ciofi disc is simply fabulous - the voices complement each other beautifully, and the performances pulse with vitality. It's truly thrilling. Well, in my initial comparisons, I don't think the Piau/Mingardo versions quite match up, but they are so different that I hesitate to be too insistent on it. Piau has a very pure soprano voice, very technically perfect. Mingardo's contralto is quite deep, almost masculine - rather hard; a bit severe. So there are two extremes here. By contrast, Didonato's mezzo is softer, more feminine than Mingardo; and Ciofi's soprano is warmer than Piau. So the overall effect when they sing together is very, very different; and truly it's not easy to say which is 'best'.
I don't know if this is too subjective to be useful, but I feel I really must add that whereas Didonato/Ciofi give me shivers and thrills up my spine, Piau/Mingardo, frankly, do not. They're giving virtuoso performances alright, but they seem detached; cool. If I had to walk away with only one of these CDs, I wouldn't hesitate - I'd take the Didonato/Ciofi and leave the Piau/Mingardo behind. But whether it would strike others the same way is hard to know. If you don't have the Didonato/Ciofi disc already, then I'd say get that first, cherish it, revel in it, thrill to it; and then think about the Mingardo/Piau disc later.
