I only ordered directly once (the Emanuelle boxes, when they were on sale), and I
think I asked them to declare a lower value and they did it, but that was some years ago...
As for titles that should be avoided, I read some complaints about the Horror Express BD, but since it is a public domain title it still is the best release for that film.
Then there are the real stinkers, like Birdemic, but you can see that from the trailer alone
