Granted, most of my LA experience is confined to LAX airport and that was last summer. I wouldn't be surprised if LA proper is better, but that was the first time I saw sub-1M LTE speeds before they went online here in Missoula.
I map coverage by walking around town with Sensorly running on my Nexus 6P, and sometimes while on the bus. I'll only be able to map what's accessible on foot or by transit. I can't map everywhere and I hope someone with a car can cover the spots I can't.
Also, I would hope coverage improves, but a lot of the problem now feels like they're still fiddling with the cell sites. For example, I got my first call dropped mid-conversation today, which was very confusing because the phone said "no signal" while half the triangle was filled. And data doesn't work in parts of town. North part of town, for instance, I see solid 3G signal but data just doesn't work, so I'm effectively disconnected while I'm shopping at Costco or Target (or I would be if I didn't have a T-Mobile hotspot and a Canadian Wind SIM).
On another note, I tried to join a friend with his own iPhone 6 to my 25GB plan, that turned out a disaster, but that's not the topic of this thread.