Product review (5 stars): Works Very Well!
My dad and I tried the vent cleaner today.  We were very impressed with how well it worked.  The kit came with just enough extensions to reach the drier.  If you have a fairly large home, you may seriously want to order the 12' extension kit with it.  My De Walt 18V drill had plenty of power to spin the brush effectively.  When we started the first pass, we couldn't believe how much lint and dust came out of the vent!  There was a fire hazard lurking under my home this whole time.  We are very good about emptying the lint trap but it obviously is not enough.  A few points I observed:

1.  There are plenty of instructions included; both paper and a DVD.
2.  My small shop vac hose diameter was smaller than the shop vac attachment and I used duct tape to seal the vacuum hose to the adapter. this proved enough air flow to send all lint and dust through the venting.
3.  Make sure you check under your home to examine the condition of your vent tubing.  I found that mine had disconnected some time ago and lint was collecting under the house.  This was a good time to fix it.
4.  If you are fixing loose or disconnected venting, some aluminum metal tape works extremely well for the job.
5.  Having an extra set of hands to help move the dryer, etc, can really make the job more pleasant!

I highly recommend the cleaning system.