Although the internal breaker to the Power Plant Premeir is 15amp, it will allow far greater current through for a short period of time. Thus providing the Premier with a 20 amp line will help the Premier to perform in high demand power peaks, such as explosions.

Another reason is that running a 20 amp line is just a fraction more than running a 15 amp line. Thus, when most audio and videophiles run dedicated lines they choose to go with 20 amp lines to better accommodate any products they may use in the future.