I agree that Andy Strapz panniers work and work well.
I rode in a group of 3 all using expedition panniers and they all did well through 28,000km of bad roads and often being dropped. Mine went down on a highway at around 80-90kmh and the only damage was a small scrape/melt that could be sewn up and a broken plastic clip.
There were a couple of little issues, as mentioned above, the small straps holding the panniers in to the rack didn't last long. Though we accidentally came across a solution, rather than sewing the strap on we used velcro, but still kept the plastic clip. So when they hit the road, the velcro let go before breaking anything.
Also the seam where the main straps are sewn into the end seams (obvious place once you see them loaded up on your bike) began to let go. But some time with a needle and fishing line fixed that up nicely.
Andy is an easy and helpful guy to deal with, both when choosing stuff and subsequent service.
Vladivostok - Denmark 2008... Finished.
Denmark - South Africa 2010-2011... Finished.