Product review (5 stars): Dryer Vent Cleaner:
The price was good and they come very quickly.  Ordered extra extensions as we have a 30 foot run in vent.  Dryer(thank goodness it was electric, as a gas one would have burnt the house down) was taking hours to dry and then cloths still damp.  Comes with attachments (I did not use),  Started cleaning from dryer down to floor level and going through four 90 degree turns and got a lot of lent out.  Turned dryer on air only and went out side and went 3 feet at a time in and then remove.  The lent came out and I would add another 3 foot length and repeat the process.  After going in about 24 feet I was blasted with last blockage.  Cleaned up a bag full of lint (the attachments would keep things clean but is a hassle (my estimate) to use).  That was 15 years of build up of lint.  Never knew to do it till sister-in-law paid over $100 for someone to clean hers out and said how much lint she had.
I plan on doing this once a year to keep it clean.
By the way, drier now only has to run 30-45 minutes or less to dry cloths.
I would recommend this product.