Like most spray foams, this stuff is very sticky and a bit of a mess to work with, but it is excellent to fill larger gaps where caulk would not work well.  I use caulk when I can, but sometimes I need the foam.  Where I am using it the trim will cover, so the color doesn't matter, but the black could be a big advantage where it would be visible.  I would say it expands to 2 or 3 times the original volume after application.