Hello, I just got a new iPhone and I would like to minimize the wear and tear on the battery. If I get myself a Mophie and leave the pack always on, presumably the brunt of the battery wear and tear (and charge cycles) will lay on the Mophie's battery, as opposed to the iPhone's battery. Only after the Mophie's battery is depleted will the iPhone's battery be used. Anyone with any experience using the Mophie 'always on'? As opposed to following the 'official' recommendation of letting the phone run down to 20% before charging using the Mophie. How does that work out? Presumably this is also the simplest way of using the case...just keeping it always on. I wanted the official apple battery case originally..but at double the price to the comparable Mophie, I find that hard to swallow.... Thoughts? Thanks in advance.