The difference is a “Voltage Regulator”. The 5400 will adjust the voltage should it decrease. All other features are the same when comparing the 5300 and the 5400. Both of these units will provide superior picture quality should there be electrical interference. These units also have the same amount of power banks to plug your components which also eliminates interference from your components. My suggestion would be to save your money and purchase the 5300. Should you have issues with your electric levels I suggest having an electrician check your electrical system.