I liked Shadow best in Sonic Adventure 2. He was more calm and acted more like his age, but was still an intriguing character - no edginess needed to achieve his dark personality. With the StH game, it felt obvious that they were trying to make him more bada ss, it felt a bit forced for some reason. In Sonic X he acts like a complete dbag lol by going after poor defenseless Cosmo.
This is just my opinion on one of my fave characters of all time :-)