I'm in the camp with the others who don't use screen protectors. I tried to install them on my other phone and it almost made me nuts (if that's possible). Finally gave up (after $1652.22) in wasted purchases as I could not live with the bubbles. Had that phone for 2 yrs before my Verizon contract was up and in the end the screen was perfect. I was just careful to not put keys or change in the pocket with the phone. That was easy for me as I have not had change in my pockets since banks came out with debit cards.
I do use a case, though. To protect the phone but more importantly for me was to make the phone thicker. I have no clue why all these mfg's keep bringing out thinner phones every year. I can barely pick them up now they're so thin.