The Alecia Keys Library from NI - I have not heard, however the vids and promo material is drummed up in the perfect environment, mix and effects.
But the biggest thing with any piano is the reality conveyed by performance of the actual player.
If you don't know how to play piano then it will probably still sound a little bit fake or unreal regardless of what you use.
Ive used Reason Pianos and have done some decent stuff, but Ive got a friend I work with, who actually plays piano and his work on my set up using the same gear sounds far better.
You also should know that a piano is not a dead instrument and it dresses well with reverb. What type of reverb and its settings depend on the "stage" that you put your piano on. Are you going for a large venue sound, a small club, a room in your house, a church ect. . . . .
A tight, slap back delay and short decayed, reverb brought down low does wonders in sounding like a small live venue.
Once placed in a good mix, the details of the piano are less important and only stand out on solo/quiet parts of the song. Which is probably going to be covered by singing or rhyming anyway.