These are happening more and more in our part of NW London. It seems like a good way of getting several viewings out of the way in one day - but do they actually yield results. I went to one about 15 years ago for a small flat though the market is obviously more challenging now.
Are you meant to be present? Is it still via appointment or do they basically leave the door open for the afternoon? Is it likely to result in a quicker sale or do their usual bunch of developer cronies put in an appearance to make up the numbers?