FWIW, I've noticed more issues with VZW iPhone X and weak reception than any iPhone in recent memory. Just some of the common issues: falling back to 3G and refusing to re-initiate LTE coverage (unless I toggle airplane mode), 1x coverage showing up and persisting regardless of changing location, 1 or 2 bars of LTE signal jumping to 3 or 4 after toggling airplane mode. And don't even get me started with WiFi hanging on to 1 or 2 bars of signal to the point that apps indicate no internet access (typical situation: walk out of a hotel, get into car, open Waze to enter address, phone stays locked to faint hotel wifi signal for minutes until Waze gives up and tells me I have no data access - I have to manually enter Control Center and click off the Wifi, then give the phone a minute to figure out the cellular situation).
It's like I'm constantly fighting this damned phone to hold/maintain cellular and/or WiFi signal and I'm pretty tired of it, to the point I've considered giving AT&T (and an AT&T iPhone model) a shot. I've tried resetting network settings, restoring the phone as new, and tried different combinations of roaming settings and nothing appears to work. Most of my time is spent in NC, SC, GA, FL, VA, PA, and AZ, so this hasn't been a specific location-based set of issues.
I'm still on a grandfathered VZW unlimited plan (mainly because I'm being lazy) however I assume that has nothing to do with my issues, as they weren't nearly as prevalent with prior iPhones.
Open to suggestions over here.