Product review (4 stars): Works great!
Purchased from a big box home improvement store because I needed it asap - but the $25 Amazon price would have saved me $10!

Using this to clean my dryer vent pulled out a ton of dense damp lint. I used a manual feed, and found using the drill to be ineffective. This is easy to use, though it only comes with 12ft of rods, and our dryer run is 24ft+ so we needed to get the extension kit.

Note: if you have a long run you will most likely need a shop vac or leaf blower to use this effectively.