pvrnyc

I'm finally putting together a home theatre system (a 5.1 setup to be specific) and am wondering which rear speakers, subwoofer and center channel I should use to match up with the KLF-20s that I've had for years. I need to use wall mounted speakers for the rear channels, so I thought that perhaps I would use a pair of RSX-5s. Since the KLF-C7 is no longer available I thought I might use the RCX-4 for the center. For the subwoofer I thought I would use the RW-12, although I can't even guess what crossover freqency to set with a setup like the one I've described. Anyone out there have any ideas, especially better ideas? Is the setup I've described likely to sound unbalanced?