I called A-Z Air Duct because my dryer was taking a long time to dry. I know that I had not had the dryer vent cleaned in 13 or 14 years. Two great guys form A-Z Air Duct came out and spent well over an hour cleaning the dryer vent. My dryer vent had a very long run and was exceptionally dirty and clogged up. I was very surprised at their determination to get the dryer vent cleaned in one visit. They worked really hard and pulled out all the tricks in their book to get it unclogged and cleaned. I think my dryer vent was one of their most clogged and difficult ones that they have serviced. I would definitely recommend them to anyone looking for dryer vent cleaning. I also will start getting my dryer vent cleaned regularly.