I would only use the dcx on the subs, and not on the mids/highs at all. I have dual outputs from my preamp, so the sub signal is comletely separate from the mid/high signal, and I'd still be using the passive crossover for everything except the under-200hz stuff.
The bass with the V2's is FAR better than any other (box) speakers I've used, but it could still use a bit of eq to deal with the left speaker loading the room a bit more than the right speaker. And the controls on the SA1 amp only do gross volume adjustments, and no eq.