well, in my point of view, ghosting is surely not something recommended unless you really know how to blend it in.
Most people (new wallers especially) take a bunch of screen caps and paste a chosted image on top.
I myself started a few walls back a year ago, before I dwelled into walling more professionally with ghosting walls. And
well, these personally were never shown in minitokyo and frankly, they were teh sh*t.
The reason why ghosting has a generally bad image is cause of its cheap effect like appearance. Much like how clouds
render is never a good thing until you really learn how to use it.
Now, ghosting itself is not bad, but most images ghosted upon are usually blown up by several 100x times, this highly
decreases the effort and quality, if you do ghost, I would always suggest getting a uber large scan to play with,
extract it nicely, clean it up and then use it.
Until a waller can understand the uses and importances of executing these effects, ghosting will always have a bad name.