i live on a rural area and given the antenna locations around my house, in most areas of my house all i can get is a fraction of a signal bar on my iPhone. as soon as i get to an urban area there is plenty. i know there are wireless cell amplifiers to boost reception and transmition, i have seen some on display and on the web bUT never in operation. the sellers claim fantastic performance, customer reviews give a lot of stars. the prices range from $300 to $600 Has any of you purchase and use one of this devices with your iPhone ?