Diaperchic, the paint does not HAVE to be heat set. Heat setting melts the paint into the fiber so it does not fade when washed. I have spilled all kinds of paint, fabric and non fabric, on my pants and shirts, never heat set it and it DOESN"T wash out

So to answer your question, any fabric paint will work without heat setting and if you let it dry for a week, before washing it may not fade, but probably won't last as many washes as it would if properly heat set. If you are charging money for the work done on fabric, it needs to be properly heat set or you will have some angry customers. Do some tests, with the paint you have available to you and see how it holds up. Golden Fluid Acrylics say the do not need heat setting but will hold up better if heat set. I know what I spill is still with me!
