Personally I prefer GG3 over 4 or 5. Now that nearly all new phones have this 2.5 curved glass it's nearly impossible to find a tempered glass screen protector that fits properly. GG3 is harder and more scratch resistant which is what is needed when you can't find a good glass screen protector. GG4 and 5 are more flexible thereby being more shatterproof (although it's really not that much better if the phone falls on its corner without a case). But being more flexible and plastic-like also makes GG4 and 5 more prone to scratches! So for me I wish all phones had FLAT glass so no matter which Gorilla Glass is installed at least I could get a good tempered glass screen protector for it!