I have it from very reliable sources that the resolution of the L3 MMW scanner is about 10X better than the published image, and the artifacts are pretty much gone. TSA will not allow L3 to publish a higher resolution image, as they have an agenda, primary of which is not to scare the kettles.
All cases where the press and others are allowed in the resolution room are simulations, specifically designed for the press and the kettles.
My guy says "you would be shocked by the current state of the art". The images you see are 5-7 years old, and after more than 50 software and hardware upgrades, and $10M in R&D, they approach the Rapiscan in resolution (about 0.1mm).
The Rapiscan resolution and image processing has also improved, but not as fast as the L3. Of course TSA is hiding the images, but some will leak eventually, and that will create quite a furor. ^