The Genesis version of Soldiers of Fortune is leagues better than the SNES version. The dithered graphics suit the game's art style better. It is much smoother too. Same goes for Thunderforce 3. I know the SNES version was a port of Thunderforce AC, but it is lacking in every way. Genesis got the better Darius game (Sagaia) as well, though I did still enjoy Darius Twin quite a bit. Super Nova is weak.

As mentioned before, The SNES SFII games ran rings around the Genesis versions. Better sound, larger characters and more colors. On the flip side, I wholeheartedly agree that most of the SNK Neo Geo ports were better on Genesis. Also, even though it was badly censored, the SNES version of Sunset Riders was truer to the arcade game. The SNES port of Turtles in Time also slays The Hyperstone Heist. Super Ghouls & Ghosts, despite its slowdown, looks much better than the Ghouls 'N Ghosts on Genesis.

When it comes to the early polygon stuff (choosing to forget the Tengen ports of the early Atari 3D games like Steel Talons (which is better on SNES), Stunt Race FX is not even in the same ballpark as Virtua Racing, but that is more due to the Hitachi SH1 than anything else. Stunt Race is higher res, but has a terrible frame rate that makes it nigh unplayable today. VR was tight and remains so.

Anything that required moving many sprites simultaneously benefitted from the Genesis's faster CPU, but anything focused on detailed sprites was much better on the SNES due mostly to the superior color palette. Genesis could excel in the area of detail when the color palette limitations were worked out correctly (Gaiares, Castle of Illusion, Sonic), but the dithering is tough on the eyes after experiencing the newer consoles. Sound was also generally better on SNES, with the major exceptions being those games that maximized the effect of the Genesis's grungy PCM (All Tecnosoft games, Sonic).

It is a wash. that is why so many of use have chosen to collect both!