Do you really feel plaque on your teeth with your tongue after brushing gently with a soft brush? My teeth feel perfectly clean after brushing despite using the brush with the softest bristles I could find (Meridol extra soft). I'm brushing gently (sweeping from bottom to top) with little pressure. Regardless of the brush you're using, never use more than light pressure. If the brush looks worn out after a few weeks it's too much, if it looks new after 3 months (recommend change interval) you're good.