Thanks. Since my first post I decided to do some objective testing for myself, so I picked up a couple USB multimeters in order to check voltage and amperes directly while my power banks are charging. One of the objectives will be to compare a solar panel’s name (a number in a name is just a name) with the actual output of the panel under ideal conditions. For that, optimal solar conditions are required — solar noon, clear air, etal. I’ll post my results here. My old GoalZero Nomad 7, the RAVPower 16W, Renogy E.Flex5 and and a recently procured Renogy 21W the will be first since they’re available to me. But that should be enough to see a pattern if one exists.

A couple things gave me the idea to do this, one was the BigBlue 28W specifications: