Get the 2.8 version (adds hardware integration for the Korg Keystage and more). Wait for a holiday sale (rare, but Spectrasonics sometimes offers 20% off through dealers like Sweetwater or Thomann).
Here’s a comprehensive, balanced review of (commonly referred to as Omnisphere Full ), written from the perspective of a music producer or sound designer. Omnisphere 2 Review: The Synthesizer That Does (Almost) Everything Verdict: 9.5/10 Essential for professional composers, overkill for beginners.
A classic. Overwhelming, expensive, and utterly inspiring.