I like open discussion, too, but when people inevitably start crossing that line, people stop posting for-sale items because they don't want some self-appointed Internet appraiser to shit on their thread and hurt their chances of a sale elsewhere.
Classified forums are the lifeblood of a forum--they bring the most people by far--and we need to keep them fair for everyone involved, including sellers. For this reason, I think those forums need to be held to a higher moderation standard than the rest of the site. Perhaps we will allow criticism of dishonest behavior as well. I consider a shitty respray to be dishonest if it's advertised as being a tip-top truck.
I'll talk with Dave about it and we can come up with something.