First real stand was Target. Improved most parameters...some. Then moved onto Quadraspire SVT which really opened up the mid-range, controlled the bass, gave a nicer sound stage, blacker background and faster attack of vocals and instruments.
Then came the Quadraspire Reference X and everything was greatly energized. All aforementioned parameters improved with increased impact.
The real shock was moving my wife's system from an IKEA teak bench to a Quadraspire SVT. Night and day performance. You asked.