Frankly, bro.
You don't want an iDevice implanted in your dashboard tempting someone to smash your (very expensive) window to grab the (soon to be out of date) gadget.
Better to try one of those windcreen suction cup devices than ruining your interior design (and the resale value) just to make it look more "iCool".
Cheaper and easier to install and cheaper to replace with each new iDevice that comes out.