we were on pentewan last year. It does get busy and there can be groups of youths who get a bit " boistrous" after a few in the bar, but on the whole its a nice site.
Lots of evening entertainment in the bar up stairs , a pleasant veranda to sip your pimms on as the sun goes down. The beach is large and safe. Take your bikes or hire them in pentewan as there is a lovely and very safe bike ride along the old the clay train route.
The swimming pool is okay bu it can get crowded. Last year there was group running scuba lessons.
There is a local market, just up the road, a fantastic chi pshop in London.
It can get windy as its flat and come straight off the sea. If you get a beach front beach you get a wide views of the seas, but you can get other campers walking past your pitch to get to the beach.
Book it and go is my advice.