I use the brushes that Carol Marine uses and I love them, a synthetic flat with a nice sharp edge and they lay down a beautiful stroke, but they don’t last forever. After a few months the edge starts to curl and flair out making a fuzzy edge. So what do you do with these? Save for a time when you need to scrub an area? Toss them? Donate them to a youth art group?
I paint in acrylics and wash them after each use with The Master’s Brush Cleaner and I know its not paint build up. Its actual curling of the ends.