Product review (5 stars): Easily pays for itself in dryer time!
Wife wondered why our dryer was taking longer and longer to get clothes dry and the basement was warmer than ever.  Noticed that the dryer hose seemed a bit taut when running so checked out the airflow at the vent.  Was certainly lower than what I would expect for as much pressure the dryer was putting on the hose so I figured there must be airflow obstruction/restriction.  Took all of 30 minutes to run brush per instructions from both directions and 16 gal shop vac was 1/4 full lint!  Needless to say - happier wife, happier life.