i have just noticed some small dark spots in the blade and i did have a small wobly blade but for some random reason it has stopped :-\ :P ::)
My Mace had a wobbly blade problem too, and after I left it alone for a while, the wobblyness went away. Or at least, it felt like it went away.... ::) For the dark spots, if you've had the same batteries in your FX for a while, you can replace them, and it should make the dark spots go away, or at least less noticeable.