Apple maps wasn't so good at first for my local area - many addresses were inaccurate. That has improved significantly.
I commute a lot every day and switch between Apple Maps, Google Maps, Garmin, TomTom and Waze.
I prefer the aesthetics of Apple Maps over Google Maps. However, with both my 5s and my 6, Apple Maps has a slight lag. I will have already passed a street and the map will show me approaching it. When I stop, Apple Maps catches up. There is only maybe 3 seconds of lag, but its there. This does not happen in Google Maps.
I am very OCD. Either one should be just fine for most people.
I've used the Navigon app since it was released many years ago. I still prefer it, but Apple Maps works very well for me too. If I'm just checking something quickly, I'll use a Apple Maps. For navigation, I use Navigon &0% of the time.
I never even bothered to download Google Maps when it moved to the App Store.
Well, on my motorbike I swap between Apple Maps (for when i kinda know where i'm going but it'll notify me at a turn etc anyway) or CoPilot. I do use google maps occasionally but usually only if i can't find a specific place/not on Maps.
Used to use google maps which is still better for things like public transport and finding locations but I am starting to use apple maps more and more, mainly because gmaps still hasnt been updated for the 6s screen but also because navigation is much nicer on it...