I have tried many SP (Zaggs,Ghost Armor, ebay, etc) and non of them come close to the quality and feel of the SGP Steinheil Ultra Crystal. You can not tell that it is there at all. With the Zaggs or Ghost Armor you can always tell the SP is there cuz both of them suffer from the 'orange peel' effect. The 'Ultra Crystal' is like having another layer of glass.
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