I've had a few on there. The only one they ignored was where I slated the site. I think it might have been my complaints about goose poo at this particular place, which was a real problem, but I never found out why they wouldn't post it.
I have loads on there... in peak season (and i reckon with all the lovely weekends we have just had now is it) it can take a while... weeks even months
also dont just put " we stayed here, didnt like it, wouldnt return and the owners were rude"
instead write "we stayed at this site, despite arriving during the advertised arrival hours the owners were not particularly helpful and seemed inconvienianced by our arrival. The toilets did not appear to be cleaned (the same piece of loo roll was on the floor all weekend) the showers curtains were mouldy and the shower was more of a trickle of cold water. The bins were over flowing and did not seem to be emptied which attraxted lots of wasps. I would love to return to this area but would look for an alternative site in future" and it will be more likely to appear!