It is accurate most of the time. Sometimes, it puts your location at a place that is impossible to get into. Assume you are traveling on a freeway. If you suddenly get into a stop and go traffic, it assumes you have got onto a surface street near the freeway - either redirecting you back onto the freeway, or reroutes you to a completely different route. It confuses you if you aren't paying attention to your location.

Thanks. It's difficult to judge unless I actually test it out - I'm in the market for handsets to be able to rent/give it out as part of a broader business solution but I'd hate if the end users end up having a terrible experience.