Never been to that site, but know the area very well, and love it (mum used to have a small house nearby). We used to take the overnight ferry from Plymouth to Roscoff so that we arrived fresh, but it looks a very short drive from Roscoff (which is a fantastic town).
The site looks fantastic, good prices. I'm going to save that link, I think you've just answered my 'where shall we go' question
We've been there - we did about 10 nights the summer before last. It is adorable - lovely pitches, landscaping, facilities and just very welcoming, you can see from the pictures it has quite a unique cottage-y vibe. The owners are brilliant, the donkey cart rides and storytelling evenings are all free. I have never been anywhere like it! Obviously to get to the beach is a bit of a drive or cycle - some families were doing that but TBH it wasn't that hot in 2011 so we tended to go walking or visiting. There is a lot to do in the area.
The kids just palled up with neighbours and disappeared into the woods and hedges doing goodness knows what.
We could have stayed weeks. We are looking at going a bit further south in search of slightly better weather this year but TBH we will be lucky to find as lovely a site.