To add a bit of informations; Like told "ça baigne" is rarelly used for any young adult. To note when it's used it's often used in a more familiar's way than "ça va" (less formal)
Such way is often told;
"ça baigne mon coco"
"ça baigne, mon vieux ?"
"ça baigne, mon frêre ?"
As you can see the construction of the sentance differ a bit than a more formal "ça va".