Any drawbacks to that sword? From what I gathered, most of the unstable ingots tools all have stuffs like not yielding broken blocks. And can it be enchanted? E+ works too?
Not as far as I can tell. There aren't any proper drawbacks to many of them. The "not dropping blocks" thing is supposed to basically stop you having to go back to base because of an excess of cobble, rather than of useful stuff. It's not intended as a downside.
Not sure about enchanting, why not try it?