The purpose of a test like this is to measure visual performance, and the JPG result is performing very badly. Open these two images in a separate browser tab,

The purpose of a test like this is to measure visual performance, and the JPG result is performing very badly. Open these two images in a separate browser tab, then switch back and forth between them: http://a.pomf.se/fsnfxz.png http://a.pomf.se/fsnfxz.png http://a.pomf.se/lfzyrh.png http://a.pomf.se/lfzyrh.png Those are the upper images of the test. Also try these, the lower images: http://a.pomf.se/bgqcag.png http://a.pomf.se/bgqcag.png http://a.pomf.se/hxlwcm.png http://a.pomf.se/hxlwcm.png Again, JPG is not merely worse, but very worse. In fact, JPG makes it look like she's wearing a hat that's made of crosshatch material at the top, when in fact the top is composed of rings of fiber, not crosshatch.