Mounting a GPS

As long as it is not mounted to where it would obscure your vision you should be fine. We usually mount ours to the lower center of our windshield immediately above the dashboard. They should have something you can buy if you prefer to mount on your dashboard. I don't know exactly how to describe it though.
 
Mounted in the bottom corner of windscreen, in view of driver but not obscuring view of road.
 
They also make weighted soft cradles, in case you don't want to drill holes in your dashboard, or apply double-sided sticky tape. I'm not sure how well the weighted cradles will fare in a collision, though. Not sure if the GPS unit will stay put or go for a flight.
 
I caved in to using art supplies today over the matter. Modeling glue on the dashboard. It's never gonna come off now but at least it's up :\.

(Don't worry it's just the plastic circle the suction cup is meant to stick to).