I have mine here....

Nice and easy to see who's calling etc without taking your eyes completely off the road for too long.....
Security wise - probably not the best spot, but TBH unless you look closely you cant spot it, due to reflections on the window when its closed. If someone is interested in stealing something, they are gonna come up close and see the parrot kit wherever its installed (unless its hidden in the ash tray compartment).
When the car is parked, and the window is closed, you do need to go up close to actually notice it TBH.