Looks very sketchy to me, regardless of their claims. That soft, loose shrinkwrap stuff is the same type we used at Blockbuster back in the day to reseal used movies, so we could put the price sticker on the front without ruining covers. It tears way more easily, and feels much cheaper than the stuff used for retail releases - almost like saran wrap.
Only real way to gauge is once you do open it, whether there's any folds or scuffs on the manual or other inserts, though it's more difficult w/ DS games since that stuff is so jam-packed in there anyway.