Decent brushes make a huge difference – no shedding, good paint hold, smooth release. Synthetics for water-based, natural for oil. I stock a few sizes. Paintlab has paint brushes – angled sash, wall brushes, various filaments for clean cuts https://www.paintlab.ie/collections/paint-brushes . Got their pro set; held paint well, no marks on trim. Clean immediately after use for longevity.