I can only comment on the 300's and not the 200's.
I own both the KSA300's and the FPB300. I use them in a biamped configuration with the PFB on top. I have compared them not in the bi-amped situation, and the FPB blows away the KSA. My preamp was the Krell KBL. Go for the upgrade (but maybe with a non "C" version to save money).
I own both the KSA300's and the FPB300. I use them in a biamped configuration with the PFB on top. I have compared them not in the bi-amped situation, and the FPB blows away the KSA. My preamp was the Krell KBL. Go for the upgrade (but maybe with a non "C" version to save money).