Honestly folks..what's the difference in the sound quality of balanced vs. RCA outputs?

Some of you have probably noticed that I've been beating the boards to death about amps ever since I got my 990...but I just want to make sure I get the right amp!

The 7125 meets my power, channel, and budget needs perfectly. Of course it does not have balanced inputs. It also does not have level adjust but I'm hoping I can live without it.

But since I have the 990 I'm worried that I'll be missing something by not using the balanced outputs. Any thoughts on this? And this would only be for the center and surrounds..the fronts ARE running off the balanced outputs.