I did some research into portable power banks for laptops, and I keep finding that the Anker 737 Power Bank (PowerCore 24K), 24,000mAh 3-Port Portable Charger with 140W Output is an excellent device if you can purchase it on sale. One of my primary concerns is battery life, most of the information that I have been able to gather has this device to a lifespan of 300+ cycles. I wanted to know if Anker has any competitors, with similar specs and price point?