Now that we are getting picky, I'll ask: The "solvent" of acrylic water based paints is not so much a solvent as it is a carrier. The idea behind that type of paint is that there are tiny drops of pigment that are suspended in the water, which keeps them separated with the help of some other chemicals. When the water is allowed to evaporate and the particles are allowed to touch, they fuse into a solid sheet that will no longer dissolve in water. There are many types of polymers used in "latex" and "acrylic" paints, and some co-polymers in some "acrylic" paints. So, what I am wondering is whether, as Peteski has just suggested, there are some paints under the "acrylic/latex" water-based label that will not result in good painted surfaces that adhere well, even though they seem to mix well as liquids. Anybody have any horror stories about bad results from mixing water based paints of different types?