mig thinner?

It's very similar to an enamel base. It takes a lot longer to dry than regular mineral spirits. This is part of its design. Adam Wilder told me that its designed to give the modeler more time to manipulate a wash or filter than normal thinners.

I would use it for specific modeling purposes. It's not really designed for what you would use mineral spirits for--cleaning your brush, doing a quickdry wash or the like.