I've used screen protectors since day-1 on my Note and will never risk going without one. Not sure how the previous poster had issues w/pen response as I've never experienced this with mine - unless the screen protector has been scuffed/scratched with use. I have tried five different brands with varying success. I usually will spend about $5 or less on a 3-pack, but am currently using a more expensive one (2 for $8) from a company called Rearth or something and am pretty impressed so far. I buy all of mine from Amazon - just make sure you buy those for your specific phone as it's easy to accidently buy the ones for the international version.
Sent from my Tmo SG Note