I gave up on desktop clients a long time ago because they would inevitably crash and eat long draft posts. I haven't had that problem using the update page since autosaving was implemented.

As for mobile clients, I enjoyed using LiveJournal.app for iPhone before I moved to DW. It downloaded userpics and tag lists, and it supported my most important mobile feature, which is offline composition of posts. Like LJ/DW, it only supported saving one draft at a time, but it was easy to use.