I am ecstatic! No matter what I tried, I could not get reliable coverage for my iPhone here in my house in Chicago (Wicker Park). Complaining to AT&T; didn't help, so I was relegated to talking on my outside deck. I used to be lucky if the phone would even ring inside the house, and I could rarely actually talk from inside. With this device installed, I now get five bars throughout my entire house!I installed my antenna on the roof, three stories up, using coax from a television antenna that was no longer in use (which the instructions say will give sub-optimal performance). Presto! I now have 4-5 bars throughout the house. No dropped calls, and very good audio quality. The total distance of my coax is about sixty feet and flows through three coax couplers, which is sub-optimal. Still, it has worked extremely well for me. I have the unit mounted in the utility closet, surrounded by metal pipes and duct work, with no discernible impact.The three LEDs on the front have a lot of intelligence built into them -- the rate of the flash and the pattern of the lights tell you how well the unit is receiving a signal from the phone and the tower -- which was helpful in confirming things are working.