Very happy to see the guarantee, and it's kind of a shame they can't do it in the stores, but of course, you can simply refuse to buy if the manual/cover aren't included, so I guess it's not a total loss.
Now myself, I usually buy new games, so I only buy used if it's something I missed that has become hard to find. I might like to pick up the Star Ocean games for PSP though, as I missed them on Target's clearance around here. Probably GoW:Chains of Olympus too.