Tim, I havn't stayed at the site for a number of years, perhaps 10 or more but living in Dorset go past it a few times a year.
The facilities were fine when I was last there but don't want to give you any duff gen so can't say what its like to stay but looks fine from the road. The site is at Seatown which has a large pebbled beach,, common for that area ,and is only 150m or so from it. There is a small creek that kids spend lots of time in, making dams etc. There is a pub ( the Smugglers I think) and you can walk to Golden Cap if your feeling fit. It really is a beautiful part of the county, Brideport, West Bay & Lyme Regis are all easy to get to. I can recomment Highlands End at Eype just along the coast but it is at the top of the cliff and perhaps 1km from the beach via the coastal path.