I really think after mulling over what his role would be on the C's (unless Ray Allen wants to become a 6th man ala Ginobili), he's going to seek greener pastures.
At least on the spurs he'd be a starter, and also have a chance at a bigger payday down the line like you said Marcus.
I was skeptical about Corey Maggette at first, but sounds to me like he's not a me-first type player like Gilbert Arenas. I'm confident he would find a niche on the spurs that both he and his teammates would be comfortable with.