Product review (3 stars): Shreds vinyl vent hoses
The only thing this helped me to do is to confirm that my dryer vent was clogged with lint.  I used it as the directions describe it stirred up a lot of lint, but it also punched holes in the vinyl tube and shredded it. This happened on both ends of the vent, near the dryer and near the outlet.  I ended up having to replace the whole thing with a aluminum in a very tight crawl space.  I will keep the linteater for the future to clean out my new aluminum tubing, but if you have vinyl, not sure it will be of any help except to make you replace the vinyl with aluminum.