Well, I think you could say that about alot of the classic oldschool games of that generation. It's personal preference, really. The Sonic games really made full use of the Genesis' sound engine above almost any other game on the system, and I have no problem saying that they easily rivaled the sound produced by the SNES. I think that's why we all love the music from those games in particular.
On a side-note...I love how this topic went on the tangent of why we loved the old Genesis Sonic games. (and consequently why this new one should really stick to the precedent set by those games)