Tech21 Impact Shield
Last but not least is the Tech21 Impact Shield for the Galaxy S8. Tech21 is one of the few companies in this list part of Samsung's partnership program. Meaning you know the end result will be a finely tuned and precise screen protector for your phone. Samsung approves each accessory before it goes on sale.
Tech21 uses BulletGlass, the same type of technology used in bulletproof glass. It's similar to the strengthened and hardened glass from others, but really fancy. It covers from edge to edge and should be very scratch resistant.
Each screen protector comes with an installation tray for ease of use, which many will enjoy. It's also made to work with Tech21 cases or any case for that matter. Meaning the final fit will be just small enough to keep your screen safe, while cases won't pull it off.