I just noticed a snag in both versions: you'd hav to erase Sonic out of every shot. The Genesis version will let you use an emulator and turn Sprites off, but that defeats the purpose of sprited maps. >_>
Also, since some people here are clueless as to version differences, I'll post a few screens. Credit to The GHZ (http://www.theghz.com) for these, because atm I'm too lazy to make actual screenshots of my own. This will not be friendly to slow Internet connections, I warn you (but is anything anymore?).
(http://www.theghz.com/sonic/3d/3d_03.gif)(http://www.theghz.com/sonic/3d/saturn_01.png)
(http://www.theghz.com/sonic/3d/3d_06.gif)(http://www.theghz.com/sonic/3d/saturn_02.png)
(http://www.theghz.com/sonic/3d/3d_11.gif)(http://www.theghz.com/sonic/3d/saturn_03.png)
(http://www.theghz.com/sonic/3d/3d_14.gif)(http://www.theghz.com/sonic/3d/saturn_04.png)
(http://www.theghz.com/sonic/3d/3d_18.gif)(http://www.theghz.com/sonic/3d/saturn_05.png)
(http://www.theghz.com/sonic/3d/3d_23.gif)(http://www.theghz.com/sonic/3d/saturn_06.png)
(http://www.theghz.com/sonic/3d/3d_26.gif)(http://www.theghz.com/sonic/3d/saturn_07.png)
(http://www.theghz.com/sonic/3d/3d_29.gif)(http://www.theghz.com/sonic/3d/saturn_08.png)
(http://www.theghz.com/sonic/3d/3d_32.gif)(http://www.theghz.com/sonic/3d/saturn_09.png)