Re: Actually most satnavs are still remarkably unreliable
"Last weekend, driving round Birmingham the satnav (recently updated by Honda) took us to a Tesco, which turned out to be the one that closed three years"
In general, reviews I have seen of in dash satnav systems provided by car companies have reported they are both quite inferior, and very expensive when compared to systems from vendors of dedicated satnav devices.
For that matter. I find dedicated satnav devices significantly more usable than smartphone implementations.