I really liked Dark Brotherhood. It had ridiculous low quality in some stuff, such as music, some animations, and the progression challenge level was all over the damn place (stick to WRPGs, Bioware. JRPGs are not for you). But it was the ONE Sonic game with a good story, ever. Once you went into space it truly felt like a Bioware game, the choices seemed good, although not giving you much room to pick, and the enemy design and environment was cool.
They shouldn't have had the trainee team take over the game. That was pretty much an excuse to make a quick buck at Sega's expense. Their "DS development studio" is never gonna make another game again.