One pair for the inputs and two pair for the outputs, correct?
yes - if you are sending one pair of i/c's from your preamp to the dcx, & want to send two pairs of i/c's from the dcx to two stereo (or four mono) amps. (you're bi-amping?)
re: taking a "local look", i suggest using the fone first, instead of driving around to different shops.

doug s.