Product review (5 stars): Does a fast impressive job.  Worth the price.
This definitely did the job without my having to go on the roof.  I was impressed that it snaked through 2 tight 90 degree bends and cleared about 16 ft of dryer flue effortlessly.  Attached a Shop Vac to the lower end of the flue and that sucked all the free lint out easily.  Quibbles?  Could they include an extra 4" brush?  There's just one, which has only one or two rows of bristles.  I'd like to clean twice per year, and feel that the single brush might only survive a few cleanings.  The rest of the system seems very robust though.  Delivery was prompt.