It depends on the maximum power your device can draw. If your device can only draw a maximum of 15W (for example: Moto G4 Plus), TurboPower15 will be sufficient as the 25W charger cannot provide faster charging. i.e. Your maximum 15W capable phone charges at the same rate using either 15W or 25W chargers. However, if your device can draw full 25W (for example: Moto X Style and Moto X Force), TurboPower25 will be the choice.
