I using anti finger print type protector, so far no issue using swipe.
Last time when using clear type always Jam my finger half way.

Btw I saw China got sell type that cover whole screen not sure how good is it cause some times there have size issue.

Drop my n9 yrsterday and dent a bit my right upper corner, heard pain.
Dam Hard to find n9 casing at local here, some even selling insane price.