Product review (5 stars): Worked Like a Charm
The LintEater worked like a charm. I thought I had about 20 feet of dryer duct to clean so I opted not to purchase the extension kit. I figured I'd use it from both sides so the 12 feet that comes with the kit should suffice.

I didn't purchase the optional lint bag but found a cheap alternative. I duct taped a garbage bag to the side of the house around the end of the dryer duct but leaving plenty of opening for air to escape from the bag once I turned on the dryer. I then cut a slit in the bag to get the LintEater through. After about 10 minutes of running the LintEater while the dryer was running, I was done. I didn't realize it while I was using it, but the garbage bag was almost half full when I finished. I didn't think that much was going to come out. If I didn't use the bag, then I would have made a huge mess in my yard and the neighbor's yard.

I recommend reading the fairly well written manual. There are some tips in there that may not be obvious that will save you from a big headache. I also recommend a dust mask while doing this.

I used an 18v cordless drill with a 3/8" chuck.