I was having problems with WP Super Cache, which I think I have now resolved with a complete uninstall/install; the only remaining peculiarity is that I seem to be unable to deselect 'Clear all cache files when a post or page is edited.'
i.e. I uncheck the box and hit the 'Update Status' button, but it selects itself again. I can change the other options - turning caching on and off, for example - but not that one.
That's not necessarily a problem: the site's not very active, and the plugin is really only precautionary, so clearing out the cache all the time may even be the best option. But, you know, it's peculiar and slightly irritating, so I thought I'd mention it.