Wow, those covers are sweet. I wish the screenshots in the back were of better quality though, especially in the Double Dash cover, where it's most noticeable. Also, and this is really a minor thing, in your MP5 cover, the tip of the starman, which would end up wrapping around to the spine, is cut off instead. I personally think it'd look better if it wasn't cut off. I like covers that wrap around that way.
I'm no quality assurance guy, so I can only tell you what I see, not what the site demands. Still, I can't wait to see what else you whip up.