I think the Turbo is able to deliver good chip generated music if done by talented people. Gradius, Salamander and R-Type are very faithful to their Arcade versions. Bomberman 94 is just pure joy for the ears. I've got mixed feelings for Blazing Lazers' music, though.
The Turbo's Redbook audio can be nice if accompanied by good sound effects.
SNES' music is a hit-and-miss. Some games have outstanding music that couldn't have be done anywhere else without redbook (Terranigma comes to my mind), while there are still lots of games with boring or even really bad sounding music.
I have no clue of the Genesis' music capabilities aside from Sonic 1 & 2, Rocket Knight Adventures and Jurassic Park.