Looking to pick up an on-board charger soon. Looking to run the 55PD from one 27 series, for now anyways. Question is this: I found only 1 charger that can be used for either 1 or 2 banks. All the others are designed only for a particular setup. By using a dual purpose charger, is this bad for batteries? Pros/cons of a charger matched to number of battteries? This is new territory for me. Thanks.