Both Windows 7 Phones on my US Cellular account were great. Unfortunately they died of old age right at the time US Cellular was abandoning Chicago, so I moved to Verizon and gave the HTC 8X a try.
In addition to dropping calls, during a conversation where the contact name or phone number is displayed it would change to "In Call" and then go silent in both directions. The only thing I could do was hang up and try again. Nobody at Verizon's second level support had any idea what that meant. And sometimes when I tried to send a text, words to the effect of send failure were appended to the message followed by a link Try Again. You could try again forever and keep getting the same failure. Sometimes you could immediately retype the same text and send it, but the failed one would never go out. And every now and then, usually more than weekly, it went nuts and had to have its power cycled, and every now and then it had to be reset to factory settings.
I got a replacement, and then another one. All three HTC 8Xs had the dropped call, In Call, text failure, need to cycle power, and need to reset to factory settings problems. I never had one long enough to download any apps. Other than voice and text when they worked, I only used Internet Explorer, HTC weather, and maps.
After three failed 8Xs I asked for a Lumia 928 and got one, reconditioned of course. My favorite feature was maybe three times per week while I was on a call it would redial the number I was talking to and create a conference call for both of them. If it was a business with multiple lines I would get two calls in conference. If it was a land line with a contact that had a mobile number it would dial the mobile number for a conference. Otherwise after redialing it would hang up the first call while the second call was ringing, but the other phone was still off the hook, so it returned busy. After the other party hung up I could redial.
And it went nuts and needed a power cycle to recover more frequently than the 8Xs. Finally last night it stopped paying attention to the screen, which I could not slide down to turn off. I called 611 and got a clueless support guy who either was not trained or was untrainable. He told me a probable cause was the SD card. I told him the 928 doesn't have one. Then he told me to remove the battery. I told him it's not removable. I didn't know about this forum, so I did not read that power + volume down will shut it down. I brought it to a store at 10:01 this morning, where a gentleman who knew something showed me how to shut it down.
At least I can use it between power cycles and dropped calls, and a replacement is on order. Unfortunately I cannot get a new one. After a bad new one and three factory refurbished to like new that are all what kids call epic fails, as much as I like Windows it's more important to me that a phone ring when someone calls me, that the phone on the other end ring when I call, and that texts go in and out. Is that too much to ask of a Windows phone? Has this been a futile exercise and when the next Lumia fails should I just cut my losses and ask for an S4?