Product review (5 stars): The best thing since sliced dryer lint
It's not often I get excited about dryer lint. Well, ok, never really. But this thing was amazing. Our Samsung dryer has blown the heating element 3 times in six years because of badly clogged vents. Wish I had discovered that fact, and this product, sooner.

I connected the shop vac to one end, and ran this thing from the other. About halfway through I noticed the shop vac making that high-pitched noise it makes when there is a clog. I removed it from the wall to find a plug of lint exactly 4" in diameter, and about a foot long! It was disgusting, I was so happy. Hooked the vacuum back up and finished up the rest of the pipe.

Be sure to follow the instructions and you shouldn't have any issues. Namely:

1) Always make sure to rotate the drill CLOCKWISE, both going in and pulling back out. This is so that the connecting rods don't unscrew while in the vent. (The instructions suggest taping them together to further lessen the likelihood of them coming apart. I did not, and can't imagine that it would be necessary if you are doing it right.)

2) Only attach one rod at a time. This makes it a little more of a pain in the rear, because you have to keep stopping, detach from the drill, connect the next rod, connect to the drill. Go. Then stop and repeat 30 seconds later. But if you try to do more than one rod at a time, it is nearly impossible to feed it correctly.

3) Because you can only do one length at a time, you're really cleaning in 3' sections. For each 3', I recommend going back and forth multiple times to really get everything out. As it happened, I had removed a 4' section of duct about halfway through my run, because I'm also installing a booster fan (http://www.amazon.com/Fantech-DBF-Dryer-Booster-Duct/dp/B000GXF7KO/ref=sr_1_1?s=hi&ie=UTF8&qid=1441988913&sr=1-1&keywords=dbf110). This gave me the opportunity to "practice" on this removed section of pipe to see how it actually worked inside. What I found was that it doesn't necessarily clear everything in one pass.

4) You also don't want to go too fast. Think of it kind of like a vacuum cleaner on carpet: you can run from one end of the room to the other, but the vacuum will be much more effective if you go slower and allow it to grab more dirt.

Love this product. Happy lint hunting!