I use the screen protector, to guard against scratches, i.e., in your pocket and drop keys/coins in by mistake and protecting the coating.
The ghosting, was maybe a poor choice on my part. Clouding is a more accurate term. When the coating wore off on my iPhone, there was a faint but discernible clouding over the area that where it failed. Enough to irritate me.
I may opt for the tempered glass for higher protection again drops, though I have never dropped the iPhone. The IP6+ is so big however I wonder if the risk of dropping is higher so I may opt for more protection