I viewed a house that was advertised through this site. It was a slightly odd experience as a buyer. I phoned, left a message, a woman phoned me back, we settled on a time to view that was convenient to the owner and at that point she gave me the owner's number, and he showed me round.
He was very pleasant, but it was a bit odd. I don't greatly like estate agents very much as a group, but you get used to them after a while. This was very different, in that he was a nice bloke, showing you his house, while juggling a toddler. He lacked any real feel for how to sell it, and (because he was so nice) it was all a bit awkward. We didn't buy it anyway, it was too small.
That house stayed on the market for months (in an area where most places were selling inside a week). It then went on with one of the big, aggressive agencies with a higher asking price and sold very quickly.