Product review (4 stars): Buy This!
It does what it says.  The main issue that I had (or so I thought) coming into my new home was that my dryer wasn't drying as efficiently as I knew it had been.  My clothes now were taking twice as long to dry as before. The last owners probably had no idea how clogged the vent was.  It was a fire hazard, which was really my biggest issue.  I found the Lent Eater here on Amazon, problem solved.  Works as advertised, just don't get it stuck by putting your drill in reverse at the wrong time.  It works!