Went to Pentewan a couple of years ago. Good facilities ie shower block, washing up sinks. Not used the club house so cant answer for that, looked like the usual noisy beery type of place. Quite a good shop on site. Pitches are a bit cramped in some areas, but depends on the size of your van really. If you have a big twin wheeler you might find it a bit tight.
Little village right next to the site, with only one pub serving great food. Downside is that it is the only pub, so it was packed to the rafters every night.
Park is in great location if you like walking over the cliff tops, Mevagissy is in walking distance, takes around an hour.