Sonic 06 played like shit. It had a terrible physics engine. It was dreadfully rushed and it shows. However, there are SOME things it does well. While it's often sh!t on for having Sonic kiss a human, There are some good aspects to the story. Shadow's campaign imo is great story wise. It introduces the demonic, intimidating Mephiles, who reveals to Shadow that the world will betray him in the future, and that the one to bring him down will be his own teammate, Omega. We see Shadow pull together with his team and show just how far Shadow has come as a character since SA2. The story of 06 does Shadow more justice than his own solo game. (again, just my opinion)
