jagardn
Airbrush Acquisition Disorder Patient
I was advised to use the 4011 to help me slow down my building up instead of using water which raises the risk of spidering more.
One of the others is supposed to reduce the tip dry increased by the 4011 but I'm not sure which, but I think @jagardn can give you more info there.
The 4011 also lm makes the paint dry quicker which is handy for small projects so you don't have wait long for layers to dry.
The 4012 reduces tip dry. It does work well with Wicked, AA, and Createx Illustration. I personally have not tried it with any other paints though.
Since it does have a bit of solvent in it, using it with other paints would scare me a bit.