I love 'em.
After giving the Pan a good clean a few days ago, I found I couldn't close one of the panniers. (These are integrated into the bike's design, not an aftermarket add-on, and are very well made and waterproof. The bike looks very odd without them on.) So I took off the locking mechanism to see what was wrong. What was wrong was 6½ years and 45,000 miles of muck and damp, leading to a bit of corrosion in the works. The bars that clasp the lid closed were stuck in the 'closed' position.
I cleaned it all up wth wire wool and contact cleaner, and put it all back together with machine oil and a little dab of grease where it looked like a good idea. It now works as good as new, which is rather satisfying. The mechanism itself it a minor work of art. It works in two dimensions, so imagine that the pannier is on the bike, and the bike is North. From a 90° movement of the handle, one of the clasps moves SE for about 1cm, then turns due S. It moves far enough to get past the locking bar in the lid, and then moves about 1cm W to get behind it. Further movement of the handle then pulls the clasp back due N to clamp the lid tightly shut, and then the last bit of movement goes over-centre somehow so that it stays there. Meanwhile, the clasp at the other end is doing the same in mirror-image. It achieves all this with half a dozen moving parts, mainly plates with curved slots in them and pins that locate in other similar plates , to achieve the complex movement. I cannot comprehend the brain of a person that could design something so neat and efficient. And that's just a minor component of the luggage system: comparatively very low-tech.
Once I got it moving properly and with a bit of oil on the moving/sliding parts, I stood and played with the movement for a good five minutes. I'm a bit sad like that.
There's a good rule that says if one part goes, the other won't be far behind, so my next job will be to dismantle the other pannier mechanism and do the same. I intend to take some photographs and then put them on an owners' forum that I visit, for the benefit of anyone else who has the same problem. The biking community tends to do things like that, which is one of the reasons I like being in it.