The radically-advanced virtual instrument called East West Quantum Leap Silk is one of the most realistic "ethnic" instrument collections we've ever heard. Sampled note transitions and smart micro-tuning make this collection play and sound as smooth as. . . uh. . . pudding.
This is a short demo of the virtual instrument "Spectrasonics Omnisphere". It's really an amazing piece of software. The sound quality of this VST is the best I've ever heard.