Biamping? I assume you meant with one amp for bass and one for mids/highs. I get confused with the vertical/horizontal terminology. Anyway, only marginal advantage that way. Power supply capacity is still determined by bass and intermodulation distortion is relatively minor compared to speaker/room distortions. The other "possible" option of bridging the amps is not a good idea into either of the Kappa's impedance. Better to get the right amp in the first place.
Best advice I can give you is: neither. Not saying that the Kappas aren't very good, they are, but more of a commitment than you expect. Don't make me use the old car analogy. Jump a few generations to Genesis V's (do a search). Ya, it's mo money (probably 4X) and both have proprietary drivers but it's a "sound" investment for the longer run and a better upgrade path.
Best advice I can give you is: neither. Not saying that the Kappas aren't very good, they are, but more of a commitment than you expect. Don't make me use the old car analogy. Jump a few generations to Genesis V's (do a search). Ya, it's mo money (probably 4X) and both have proprietary drivers but it's a "sound" investment for the longer run and a better upgrade path.