I am a Buyer for a major regional healthcare provider. When asked to purchase portable chargers for an executive meeting, I chose the Anker Astro E3 10000mAh chargers and received tremendous positive feedback. When it came time to purchase portable chargers for myself, family and friends, I purchased the Anker PowerCore 20100, and all of us have been extremely satisfied. I can say, without a doubt, that Anker portable chargers are high quality, very reliable and have an excellent value. These chargers are great for both home and travel and are a perfect compliment to any emergency kit.