garmin sat nav yes or no

i have got a garmin sat nav a camper 890 and it cost a lot, had it 2 years and i dont know if i can trust it or not, it try's to make funny detours, from reading about it it does everything, when all we want is a straight forward trip if we get stuck in traffic then so be it but detours i don't think so what do you use.

This isn't entirely down to the make and model of satnav. A lot of the issues are dependent on the quality of the mapping data that they use (all of the main satnav makers buy this in from separate map data suppliers). If the map data doesn't accurately categorise a road (in terms of width) then it may get chosen for a route inappropriately.

One of the important things to do when you get a new satnav is to check the settings to make sure that they are correct for you. A common mistake is to set the route selection to "shortest route" - generally this will cause the satnav to try to cut corners. "Fastest route" should stop this from happening most of the time.

It's just as important to check a borrowed satnav - I once borrowed my Dad's and, after a crazy journey, discovered that he had it set to "avoid motorways"!

After my Garmin 51 calmly told me to prepare to proceed off-road in west Wales last summer, I gave up and bought a cheap 7 inch truck sat-nav made in China.You can input vehicle dimensions and it works fine. I will admit the user experience is not as easy as more expensive units,but it is OK.Cost of unit
was£75. Used since last summer with no problem.

No doubt a cheap Chinese unit will use the same map data as the big names - though whether they pay for a licence to use it is another matter! The big problem with no-name Chinese electronics is warranty - in my experience they create an illusion of warranty, but when you try to claim, it turns out to be impossible...

Like most, my Garmin has Fastest and Shortest, also Eco, whatever that means. However all modes plot daft routes over the local roads I'm familiar with. 
I want a setting that says 'Sensible'...
Al.

My Tom Tom sat nav did stupid things in Spain recently, so got out my stand alone Garmin, this was no better. Then tried Google maps, too much detail given of road names which we couldn’t verify and her voice almost drove us crazy. 
Thinking of possibly buying one I can put my vehicle size into or just use an atlas and road signs as we once did.

When we used to tour the continent by motorbike (in pre sat-nav days) all I had was a folded Michelin map in the clear slot on top of my tankbag, along with a few notes alongside that I'd written out the night before. We never got lost and always knew where we were.
Ok, with sat-navs you're never lost, but don't always know where you are...
Al.