I recently bought OP volume 1, 2, and 4 from my local comic store. But what I noticed was that there are a few minor details that differ which bugs me, since I like consistency. First off, my volumes 1 and 2 don't have a shine to them on the OP logo, which bugs me. They also say East Blue on the spine art and above the logo, which actually I kind of like, but I digress. On the back it also doesn't say "World's most popular manga" next to the Shonen Jump logo.
Honestly it's not a big deal to me, but I would like to make sense of it all. Are my volumes 1 and 2 dated copies? is it only for the really early volumes, then after 4 it stays the way it is? If anyone else's manga volumes have these same differences, I'd like to hear your opinion on this minor issue I have.