Despite it being cold and white outside I decided to see the differences between the stock and PixAero 3.77 lens today. Not terribly scientific but used the same settings and stationary H for each, using a stack of fruit transport bins about 50 yards away as the image subject in jpg format.
Seems the PixAero lens provides about 10%-20% magnification of the image subject over the stock lens. In very flat light and a snow covered landscape, using the Natural setting, Sunrise/Sunset and at ISO 100 and 1/400 the PixAero shifts color quite heavily towards blue. Using Auto WB brings things more back to true. A minor difference in image sharpness was present because the stock camera was set to a sharpness level of 8 while the PixAero camera is still set to the factory established level of 6. I'll upgrade that shortly. Playing with shutter speed and ISO provides some great results with the PixAero lens, but that occurs with the stock lens too. It appears the PixAero lens provides more accurate color rendition of the subject than possible with the stock lens when adjusting ISO and shutter speed.
Something those that have multiple cameras need to remember, you will need to re-bind the camera, and possibly the -16 as well, every time you change cameras. Do not even think about flying without doing that after changing cameras.
Something that REALLY ticks me off is this sites rejection of Yuneec JPG formatted files. Yuneec has a few things to get straightened out but for a forum that is there to discuss Yuneec products one would think it would accept Yuneec format photos. This is a deplorable failure on the part of site management.