Infinity kappa 9 or kappa 9.2?

I tend to like the driver complement of the original kappa 9 because it is what I am most familiar with, but I have heard at least two people claim that the 9.2 is a better sounding speaker. I have even considered the Kappa 8's to avoid all of the potential problems. I hope to drive these speakers (9's) with two Parasound HCA-1500's, but then hear one person who had trouble with even an HCA-3500 which specs with 8,4, and 2 ohm ratings from the factory.
Any help here would be much appreciated before adding another large set of speakers that are sometimes hard to re-sell. For whatever it is worth one parasound hca-1500 does just fine at high volume for extended periods of time on my current pair of Infinity RS-IIIa's. Many thanks in advance.