If I were you, I would opt out of the Sony speakers altogether is you're worried about SQ.
For excellent timbre matching, you can always use three identical center channel speakers versus three identical bookshelves as well. The surrounds do not need to be as timbre matched as the front three, but it's still a good call to have them close, or same brand.
I came very close to doing the Center Channel box for L/C/R using AV123 x-cs's. I think it would have done a terrific job.