Toontracks EZKeys for me. Depends on the sound you're after though. You can get some real classic grand, upright and electric piano sounds for EZKeys which all have individual velocity sensitive presets, but the more classic sounds still sound a bit electronic to be fair.
Honestly, Kontakt 5's Ragtime Piano mixed with True Pianos sounds amazing in my opinion.
With the right amount of EQ and reverb it can sound fantastic.