Brian, no need for the concern; both the Marantz and Onkyo units have inaudibly low distortion(i.e., below 1%)when operated within their designed power limits. When I mentioned mid 90s of dBs, I certainly didn't mean accompanied by significant distortion. Note that Alan pointed out above that on music(rather than pure test tones)distortion has to be greater than 1% to be audible.
Incidentally, that additional distortion rating at 10% is, somewhat surprisingly, part of an established organization's standard. It's the JEITA(Japan Electronics and Information Technology Industries Association)rating at "maximum" output, but it can also be noted that their "maximum undistorted" rating is at 1%. Some makers include that 10% number as an extra rating, but this doesn't really mean anything of significance; any amplifier will have 10% distortion if it's operated far enough above it's original design limit.
