Honestly, Im not a big fan of either. Here's why.
The color scheme is too contrasting. It clashes in a way ( no pun intended). The usual blue up top (which I love) is soothing. The lime green border works alright with it, I guess, but then add the orange-ness of either image and it reminds me of when my TV set in the eighties had a tint problem. I would go with an entirely different color filter.
The Second reason is that the second image, the close up of the pommel and guard with only a bit of blade, is more in line with the usual cover style, but it seems as if whoever cropped that photo did so too closely so that it almost seems grainy.
The top image, with the sword sheathed and on display ( can never remember what they are called) is alright. I like the setting sun behind it. It is not only symbolic of Japan in a way but also possibly an omen of things to come in Nightworld... BUT That image is off center.
Forgive my pickyness, its just that I spent some time doing professional photography and the girlie was originally a graphic designer.
Plus I am OCD.
I'd say between the two of them the one with the sword sheathed and on display with the sun behind, but its still lacking something.
Guns Don't Kill People, ATF Agents Do!