I'd recommend Mipow Powertube 5500. It feels more high quality imo and does what it does; charges on the go. But if you need a higher capacity or to charge multiple devices then this may not be for you.

I have never bought a power bank at all haha. Was really contemplating on getting a power bank just in case but for all the years I have been using smartphones, I managed to survive without one. Scared if I buy it, it will be for the sake of buying it and may not even use it at all