I generally hesitate to put up things from YouTube because they go away so quickly. I found these, and I hope they stay up long enough for you to hear them.
This is Leontyne Price singing "My Man's Gone Now." She is the point where I come to this. It's Gershwin as Verdi, if you know what I mean. She wails like no one else, and this is an excellent example of Leontyne at her best.
But does that spoil me for Nina Simone singing the same song? This is Gershwin as blues, a different kind of wailing. It works, too. Singing starts around 3'.
And so does this Audra McDonald version, Gershwin on Broadway, a place where he was most at home.
Three more different versions could hardly be imagined from three more different voices. All three are a treat. It is interesting to ponder how well this piece fits all three styles. It is at once blues, Broadway and opera, convincing in all three genres. In particular it is stunning how well he composed for the operatic voice.