I have used Maskol for many years now and have never had a problem with it on acrylics, which is my choice of paint for 99% of my modeling.
I also haven't had a problem with it on Future, but I don't leave it on for any more than a couple of days.
It dries to a rubbery finish, like latex, and paint won't bleed under, never has for me.
As for splatter effect, I use a small piece of foam, dip it
LIGHTLY in Maskol, and gently dab it onto the model.
After a few minutes it has dried, then I spray as required and remove the Maskol with a latex glove.
Great stuff. and definately worth putting in the toolbox.