I've now had my Z1 (C6903) for five days and I love everything about the phone. It really is an amazing device, except in one area for me: reception. I've been looking at signal strength everywhere I go and it's consistently lower than my other devices on the same network. Wifi performance has already been discussed, so I will leave that alone. But cellular reception on my device seems to be pretty bad. Consistently when I'm with my wife and checking her phone (Galaxy S4) she will be on LTE and I will be on HSPA+. At work, my iPhone 5s gets an LTE signal where the Z1 only gets H+. Where the two phones both get LTE at my house, the others are 8-10 dB higher. I'm not going by signal bars, I'm going by the dB reading.
Has anyone else experienced this? I bought this for T-Mobile and it doesn't have wifi calling, of course, so when it loses signal in the middle of my building I'm really up a creek. I really, really want to keep this device! Would love to hear others' experience with the cellular reception aspect.