Product review (5 stars): Actually made cleaning ducts fun!
Except for the direction manual, which could have been a little more clear in some places, everything about this kit was wonderful.
-- As long as you follow the directions on tightening the rods and securing with electrical tape you should have no issues with the rods unscrewing and becoming lodged in the duct work.
-- The auger brush did an excellent job at cleaning a duct which looked like someone's clogged arteries--full of lint, leftover bird's nest, and much of this material was soggy and wet in places, as well as part of the duct somewhat rusted.
-- I'll be using this every year to help prevent drier-duct-related fires

Additional Tips:
-- If you have a long stretch of pipe to clean (ours was over 21') and the vent is on the 2nd floor, this is a 2-person job.  Connect as many rods as needed to cover the whole stretch of the duct.  Have one person up on the ladder holding/guiding/stabilizing the rods at the point of entry to the house, while the other person is down on the ground with the drill keeping the extended rod as straight as possible while slowly moving in toward the ladder and then eventually handing the drill over to the person on the ladder.
-- Don't assume a once-and-done cleaning, particularly for a duct which is heavily clogged.  Go over the whole duct numerous times with the auger brush, blowing from the inside with a leaf blower after each time.
-- Once most debris is cleared, go over the duct again (again coming at it from the outside) while at the same time using an electric leaf blower attached at to the inside start of the duct using (of course) duct tape :-)  You'll end up dirty, but you can tell by the amount of debris flying out when you've gotten most of it and it's time to call it quits.