Yes it should be, I'm just disappointed with the expected recharge speeds. 2x2A, or 2.4A or 3A input.
The Powercore II 20000 is dual input. The Powercore 20000 is not.
The typical member here won't care, I'm thinking corner cases and extremes. For example: solar. The sun varies, if you get a perfect situation the 21W Anker solar panel can exceed 2A output, with the possible Powercore 20000 it would potentially discard energy from that perfect few hours. A Powercore II 20000 does not discard anything as dual-input. It is rarely perfect solar, most of the time <2A so most of the time the Powercore 20000 is fine.
From what I see, the Powercore 20000 has no inherent reason to be expensive, it would be my prediction to be the most commonly best value 20000 mAh.