We've got the Baja 540 and I had a hard time trying to decide on its mounting location too. Thot long and hard about sticking it up between the visors, but figured I'd just hit my head on it too often and it was more visable from the outside. I ended up putting it on the center console as you can see from the photos.
Looking from the back.
From the drivers seat.
I like the location so far and it doesn't block any of the vents. I lose one cup holder, but there are three others and I can still put small stuff in the semi covered one.
Whatever, just what I did. Now if they only had maps for Baja....