AT&T service at my house is horrible. I have a M-Cell in my house. I can't wait for this, so I can turn this silly, yet required device off. Worse part of this is, even with the M-CELL in my house, if I start a call on it and leave, it gets dropped and if I want to finish a call when I get home, it also drops. I believe there was suppose to be a one way handshake with the M-Cell, but neither way worked at all in my case. I am hoping that WiFi calling will be better, but I am not holding my breath, but time will only tell once AT&T gets this up and running.