The display on the Gear S is GG3, not GG4. My Note 4's GG4 and I haven't used a screen protector on it for the nine months I've owned it and (knock on wood) the display is blemish free. For the Gear, I've been using a screen protector on it since I got it. Here's why. There can't be a possibly worse or more exposed to damage location for a mobile device than one's wrist. Unlike my phone which is holstered or placed face up/down near me my Gear's subject to being smashed and scraped against things whether I'm doing something strenuous or non-strenuous. Here's how I know. My ArmorSuit protector is "self healing" meaning when it gets dented or scraped it reforms. At the end of the day the number of hits my Gear's display has taken that are waiting to heal is scary. I have no idea whether GG3 would have defended itself but I decided early on not to take a chance. YMMV.