I met him twice, and I got to hear him sing three times -- in a performance of La Boheme when I was in school, in a solo recital and with the Three Tenors.
He was terrific in La Boheme, wonderful as a solo artist, but by the time I saw him with Domingo and Carreras, his voice was gone. He cracked the high note in Nessun Dorma, and the entire audience groaned. They had really milked the whole Three Tenors thing by then (it was well after the World Cup.)
Still, he was an extremely gracious and cooperative artist, at least at the party following his solo recital. He spent hour at a table signing autographs, which he did not have to do (I've seen artists refuse after a performance.) I thanked him in Italian, and his face lit up, and he got up halfway from his chair and gave me a little bow. Later on in the evening, he was working the room, and when he passed by me, he smiled and bowed again, sort of saying, "Ah, you're the girl who knows Italian!" His first wife gave me kind of an appraising look over her glasses, and I didn't get a chance to say anything to him.
I'm glad I saw him at his peak, and the memory of the phoned-in concert doesn't affect my opinion in the slightest.