The SNES has an abundance of great first party games from A Link to the Past to Super Mario World. Nintendo makes the highest quality video games free of any glitches, unlike modern video game systems. The controller is great, the design is great, and the whole entire system is great.
The Sega Genesis had many advantages but the Blast Processing set it apart from the SNES. With games like Sonic The Hedgehog, Shining Force 2 and Vectorman, you could never find a better system. The creation of Sega Channel clearly shows that the Genesis was decades ahead of the competition.