First off, be warned of BOTH Reliable Carpet & Air Duct AND Atlanta Air Duct Cleaning because the same technician showed up representing both of them. I kid you not! They will tell you over the phone that they can do the job for around $70 for a two bedroom/two bath and then raise the price to $200 when they arrive. If you refuse the inflated price, they refuse to do the work. NO JOKE!
Pros: None, nada, zippo, zilch.
Cons: They are likely con-men or ex-cons, does that count?