I live in the Las Vegas valley - 89139 and Coverage in this section of town is very poor. In my home, the phone will say it's connected to LTE with 3 bars, but as soon as I try to use it, the signal will immediately drop. This problem is particularly noticable during morning rush hour, lunch time, and evening rush hour. Outside of peak hours I am able to use the service.
During peak times, I am often booted to 1x CDMA with 1 bar and internet that won't connect or often times no signal at all.
Also, my job of involves driving all over the city and there are many areas where data doesn't work at all or is so slow as to be impractical. Sometimes, toggling in and out of airplane mode will resolve the issue (presumably, phone attaches to a less congested band, but why is it not switching on it's own if the network is not usable?) Also, there are sections of major highways like 215 & Valle Verde where calls consistently drop on Verizon, but did not on T-Mobile.
As compared to T-Mobile, coverage was also poor in this section of town. However, I never had coverage issues when traveling around town. Speeds were consistently around 2mbps down pretty much everywhere (yep, that was LTE!) I switched to Verizon because I felt that I should be getting more than 2mbps down on LTE.
I am very disappointed because honestly the coverage and voice service on Verizon is slightly worse than T-Mobile here. The data is much better where you can get it but it is unacceptable that there are areas where there is so much congestion that the data is unusable.