Product review (5 stars): Did the Job
Worked like a champ.  My dryer is really old and was in desparate need of having its "arteries" cleaned out.  Having a good shop vac is important, as is access to the ends of the vent pipe.  The bottom line is that not only did I remove a ton of lint and its fire hazzard, but probably added life to my dryer by making the exhaust vent out more easily.  Worth the investment.