Product review (4 stars): What it is like to use this vent cleaner
The length of the poles helped make sure that the entire vent was cleared out, I did need the entire 12' for the dryer vent.  Attaching it to a drill helped but you do need to have a higher voltage drill to make it very useful.  I got the best results from using the scouring tool and pushing it in and out of the vent.