I use Testor and Model Master paints only, with Testors thinner. When cleaning, after a twist through a rag, I hold the brush with my thumb and index finger, dip it in the thinner and smack it back and forth with my middle finger, then wipe it off on the rim of the jar....repeat as neccessary. With the brush still damp, I draw the brush through my fingers to get the bristles into shape. Store brush up in a mug.
I pretty much only use two brushes, one fine tip (replaced about yearly) and a medium sized one for larger areas (about 3 years old now, still good).