It's very reliable (I've had nothing go wrong with it yet). Great price point for such a high capacity pack. I like that you're able to fit multiple packs into one charging station without too much hassle. Sometimes when using more than 1 pack at once if they both need to charge at the same rate sometimes it gets confusing as to what order they should get charged first etc. but this isn't something i have found anyone else complaining about so far though. So far we haven't really encountered any problems or issues while running our solar array off of these batteries. We are looking forward to building up a few banks of these batteries to help us power the office/warehouse during down times when sunlight levels aren't optimal.