Personally, I would go mono blocks every time. Bi-amping is only of value when you can put the Xover in front of the amps, and disable the speakers internal Xover. Mono blocks also allow minimising the effecter of cables. I use 1 meter interconnects from pre to mono blocks and 1 meter speaker cables. Still allows 3.5 meter separation of the speakers. Very little cable influence, actually the speaker cables at this length could be just about anything, as long as the metal is pure and not too much strand interaction. Interconnects make subtle differences can be use to tailor the sound. Also cheaper than long cables