Pros:

Looks amazing.
Feels amazing.
The weapon fits it's replacement pretty good.

Cons:

Nothing for katana.
There's only diamond-stuff.

Conclusion:

Katana is my favourite melee weapon (and I know there's no more tools minecraft to use for it), but if someone could find a solution for that, it would be awesome. And all-diamond-stuff doesn't look as nice as full iron, for example. (Could just be my own taste, though.)