I don't get any response from sellers or in the forums at all.
Although I only posted 2 posts in the forums so far I did contact a few people about their listings and assumed the items were sold because I got no response. However, I see these items relisted as you have also noticed. I do think they are real listings because the people at Potomac speedway indicated they know the guy who sold one of the items. However, it is confirmed sold by observers who know the person and yet it's relisted on the site again too.
I don't know what to make of it.