Nice, small panel with some power. It worked even in cloudy day - of course, barely making enough power to charge anything, but still, with its small size i consider it as a win situation. I do not think that it needs dual USB as it rarely make power to use both of them, especially with all new energy-hungry equipment, but it is fun thing to have. It is more of a toy than the real thing, but anyways this can really charge something in sunny day, not like those micro panels in power banks for example. Overall i am happy that i bought it, because it gave me comparison to other panels i have. Summarizing - in case of solar panels size does matters, and for real deal charging or powering something more than a phone, you need panel of size that you barely can name "portable" anymore.