With most speakers, bi-wiring will lead to an improvement in sound quality (assuming they are set up for true bi-wiring) -- sometimes a substantial improvement. Richard Vandersteen has discussed in several audio mag interviews (and, I think, on the Vandy website) that the advantage to true bi-wiring (not so-called "shotgun" bi-wiring) is keeping the electrical fields of the low frequencies completely separate from the mid/high frequencies. His own research on bi-wiring, which led to his decision to use bi-wiring on the 2Ce, 3A, and 3A Signature speakers, indicated that it is this separation of the electro-magnetic fields that causes the improvement in the sound quality, rather than anything attributable to separation of the crossover elements.
