Well, from what I can tell the Original version has the shininess as well (I'm using NullDC to play it, as I was not fortunate enough to own a dreamcast.) I like the Free Camera of DX, the missions were kinda pointless, but the character models for Sonic, Tails, Knuckles, and Amy (Though her new model clipped through the dress a lot.) were really good, they probably would've looked better had they not been flat shaded and shiny. The 60fps doesn't help anybody, but I really liked being able to legitimately own all the Sonic Game Gear Titles in one game (No SMC+, Just the original and Gems.). And the textures are simply clearer on the Dreamcast version, some are completely different though, that rules.
But hell, people could say SA2B was changed for the worse, even though it wasn't changed that much.