Im glad my measurements worked then!
I just reviewed the dates of my previous posts, and the replacement rods lasted about 7 months. I then replaced them with new ones, plus the clips and so far they've been fine for 18 months (and still working and judder-free).
The problem is the combination of the socket facing upwards, plus the fact that the Wipex rods are heavier than the originals. Really Wipex should be bundling clips with them where the sockets face upwards. Gravity will beat friction in the end, and all your lovely grease will probably help it to fall off.
I have remembered about the rust issue on the clips though, from reading it. I will now hunt for some rustproof ones.
Edit: I've ordered four (2 pairs) of these for a tenner. Different design, diferent seller, zinc plated (yay!)...
http://www.ebay.co.uk/itm/221282460295
I'll update this thread after I try fitting them.