Product review (5 stars): Strong and effective...works great. Caution if you have flexible ducting.
Works great. The only downside, and it is a small one, is that the opening to attach a vacuum hose to the vacuum adapter is meant for 2" (i think) vacuum hoses which come on large shop-vacs. I don't own one, just a small shop-vac and regular vacuum, so I couldn't use the adapter. The consequence was that as lint was cleaned from above it just fell out the bottom of the vent onto the floor. I just set my vacuum hose down and let it get as much as possible, stopping every once in a while to manually clean up, but it did make a mess. Again, this is a minor complaint, but a small price to pay for a job well done.

Otherwise, the tool worked very well with and without attaching to a power drill. The rods were significantly more flexible than I expected while also being very strong. I never worried about breaking them, even when I had connected many of them together (I bought the Gardus R3203612 LintEater 12-Foot Extension Kit).

The wide brush was very firm and did an excellent job of cleaning the lint out of the vents.

IMPORTANT NOTE: Because the brush is so firm, you may do damage if your house uses vinyl or metal ducting, and this is stated in the instructions. I have solid pipe, so had no issues. I did use the brush manually to clean the lint from the flexible ducting between the dryer and wall. It did not perform as well at getting the lint out of the crevices, and I can see how using the power drill and more force could have torn it open.

In the end, 5 stars. The product was exactly what I needed. Before ordering I thought the price was a little too high for such a product, but after use I believe it earned its money.