Bought a groupon for a company called Indoor Air of America and somone from US Air Solutions ends up coming out to do the job instead. Red Flag #1.
Red flag #2. The tech that arrived convinced me and my wife that if we have the ducts cleaned without a thorough sterilization of the furnace ($269 + tax) we are doing more harm than good. So, we politely ask him to leave and I called Groupon to request a refund.
Red flag #3. He told us that all the black stuff around our ducts, that I consider to be dust, is bacteria and that if we didn't have him sanitize the furnace, all that bacteria would reappear in a few weeks. He was pretty convincing but we have had ducts cleaned before and was never given this fear-based pitch.
Our goal was to help eliminate some of the dust being kicked out by the furnace, but his all or nothing approach resulted in us deciding to find another company to do the job.
One final note: I went out to throw away my old air filters while he was still here and I could see their vac in the pickup truck. It was nothing more than a glorified shop vac - not a big-time truck mounted vac like most duct cleaning companies use.