I have mine on my dash, on the drivers side way in the corner, its not even really noticeable, and works fine.
Depending on what brand of tint you have, it CAN interfere with the signal. I would recommend putting it up front, away from it, but if you know what brand of tint you have you may be able to google it and find out if there is interference. (for example, formula One Pinnacle films will not interfere, but others will)