SNES resolution:
Progressive: 256x224, 512x224, 256x239, 512x239
Interlaced: 512x448, 512x478
Genesis resolution:
56×224, 256×448, 320×224, 320×448, (PAL and NTSC)
256×240, 320×240, 256×480, 320×480 (PAL only), 256×192 (SMS games only)
I also don't see it as debatable. To me at least, the top of the line SNES games looked a lot better than the top of the line Genesis games. Also, when you can compare two versions, I prefer the SNES' games.