A few times now I've posted replies on deals that I've taken a punt on, the latest being a Sandisk Cruzer USB key misprice. Sometimes these topics are deleted after they've been up for a day or two, and when the topic vanishes it makes it extremely annoying to try and find out what happened and why.
Was it a scam? Did it just expire? Did an admin just not like the look of it? In any case shouldn't people be able to see what happened. IMHO, locking a topic rather than deleting it would be more helpful, as it is I'm often left wondering what in the world is going on.