the best shops here do a "file" method on the side windows ... using a fine file in one direction at the top of the film leaves no edge at all to be seen. looks just like factory tint. have seen this done on several cars and it is definately the way my xf is getting done. fortunately i have a very good shop near me that does tint only and the owner is the operator ... very nice facility as well and you can watch as he does the work as he has couches and flat panel with cable. ahhh now thats customer service lol.