Product review (4 stars): About time...
Worked great. Nicely flexible rods, reasonably sturdy brush, good threads and smooth assembly. I wouldn't call it commercial quality but it's plenty for mild commercial use. (apartments or similar)

For my home it snaked through 10ft of ducting then a 90 turn then 5ft then a flex 90 turn with almost no effort. The brush is actually smaller than the ducting so walks through easily. It cleans well though, since the spinning action makes it chase around the entire interior of the ducting.

If at all possible, use a vacuum with the included attachments instead of letting the dryer blow from the other. I used the simpler dryer-powered method with my too-long, lint-filled ducting, and in no time at all looked like Frosty the Snowman.

I only needed two extra rods but had to purchase the extension kit of 5. Kind of a waste. Really, if I'd thought about it I could have just worked from both ends without buying anything else. Think about that before buying the extensions.