In my Pelican case I have a four channel FFT to USB analyzer, an analog vibration meter, a phototach/strobe light, two ICP integrating power supplies, 6-8 USB cables, 6 2-pin Amphenol to BNC coiled cables, 4 BNC-BNC cables, four Pi tapes, three feeler gage sets, at least 10 9V batteries, at least 20 AA batteries half LI ion and half alkaline, safety glasses, spare shoe strings, 9" aluminum probes, one 5 " probe, two large accelerometers, 8 100 mv/g ICP accelerometers, three rare earth magnetic mounts, masking tape, an inspection mirror, and probably some other stuff, but that is all I remember off the top of my head. They are in the bag in their own spot and packed meticulously, but in no way is it neat or easy to scan. It looks on the x-ray screen like a random mess.

I variously get the following (estimates):

Case comes flying out of the x-ray right behind my computer and shoes: 30%
Quick swab and "Have a nice day": 50%
Detailed search and multiple swabs: 20%
Everything out, split into separate bins, multiple ETD swabs, rerun in different orientations, make a general mess of everything: once, when they saw the 9V batteries. (They did not care that much about the electronics but the 9V batteries were very serious.)