Product review (5 stars): Got the job done, relatively little blood
After 11 years in the house, the dryer wasn't working so hot anymore, and my investigation suggested the vent stack needed cleaning. Problem: my dryer vents through the roof, and it's a pretty long reach. Shop vac didn't do anything. Air hose from compressor didn't do anything except blow a huge amount of dust into the house. Teeny six foot vent cleaner from Walmart got only the first few feet of lint and the stack was still clogged.

I ordered this and the 12-foot extension pack based on the customer reviews and the manufacturer's video. Looked easy, and it was, relatively.

In real life, the procedure is reminiscent of a colonoscopy, luckily with someone(thing) else on the receiving end. Gotta watch out for a few things: if there's too much rod outside the vent, it can whip around and kink up on itself and almost yank the drill out of your hands. Watch out for that. Also, feeding the rod into the vent and pulling it back out is a bit hard on the knuckles, hence the blood. Great adrenaline rush though.

My dryer vent was so clogged with lint it took several passes before the cleaning ceased being productive, and filled half a large trash can with lint. Amazing.

Result: My dryer works great again, my knuckles have healed up, and the colonoscopy imagery has mostly faded away. I'll redo the procedure yearly from now on to avoid the extended ordeal caused by waiting a decade.