It wasnt a choice. Scott was kicked out.
It was more of a "I quit", "You can't quit. You're fired!" situation. Scott said "This is the last tour of Velvet Revolver" before Slash and the boys 'fired' him. And if Scott went to them right now for a reunion; Slash, Duff, and Dave would all probably agree to at least a short term reunion.
That said, Scott deffinitely made the right choice quitting Velvet Revolver. Do you think Slash would be ok writing music like Dare if You Dare or First Kiss on Mars? Scott's an artist. He needs to be free to make the music he wants to make. STP gives him that and VR doesn't.
When they first broke up and Scott went back to STP I was really excited. But then he started singing Big Bang Baby live and i lost some of that. It seems like his vocals took a huge turn for the worse after he left...He's gotten a bit better recently if he can remember the lyrics but go watch the Myspace show from 2007, he's still not even to that level yet...and the VR show i went to seemed a lot longer than the STP show i went to...maybe not, just felt like it. I hate STP's small set list
And am i the only one who loved Libertad? I liked most of VR's library to some degree...I miss seeing those songs live.
Go find an MP3 of Big Bang Baby in 2001-2002. He was singing it like that before he even left STP.