Would love to have not just the source file but also the output files posted if you can be bothered (im fine with png screenshots if you can't be arsed with actual js setup)
Sure, no problem. I updated my comment above to include a link to all the relevant files. As you'll see, despite the significant differences in file size, there is very little discernible difference in image quality.
Thanks a lot - my God this format has potential on some files!