I downloaded and printed the spec sheet for the Kyocera KC167G, that you suggested might be "almost the same" as the Shell SQ175-PC. Problem is, that the data provided is insufficient to discern if it is (more or less) equivalent.
Be aware, you can not rely on the spec'd max output from the manufacturer because those power levels are developed under entirely unrealistically high light levels and artificially low cell temperatures, all of which tend to show a false high level of efficiency .
But even were the Kyocera a comparable model, all you've managed to do is to is lower the payback period from 33 years to 31 years. Are you familiar with the phrase, "mouse nuts"?
--Boot Hill
You do seem knowledgeable about this. I am not saying that solar is feasible now, just that as the tech improves, there may well come a time (possibly in the next few years) that prices begin to drop and as prices drop, more people use it; then prices drop more due to market forces, causing even more adoption.