Earlier quoted context omitted.
I'd say it's very reliable. I'll still cross reference Waze and Google Maps, if I absolutely need to arrive at somewhere on time, but over the past year or so there's only been a very small number of instances where I thought that Apple's navigation directions were inferior to the competition (and even then, we're talking a few minutes)
It's not reliable if you're cross referencing constantly. I live outside of the USA, and Apple maps consistently screwed up to the point that I've deleted it.
Eh, I cross reference Google Maps with Waze all the time back when I used it, but I wouldn't dare call Google Maps unreliable. It costs nothing to do, so why wouldn't it?