We went to a Siblu site in Brittany a couple of years ago. It was the Domaine de Kerlann site near Pont Aven on the South coast of Brittany.
The site was large and well-equipped. There were lots of little playgrounds dotted around, as well as the central area. Here, there was an excellent outdoor and indoor pool, complete with water jets, etc. for toddlers. There was a restaurant, bar, rec rooms, and an outdoor entertainment area. The entertainment was fairly naff - but the kids loved it.
We had the largest and highest spec mobile home which was very good. We didn't have a problem with our five kids in there, but we weren't tested with bad weather. Our plot was disappointing given the van.
We tended to go out for lunch most days, and then onto a different beach each day. All the beaches are different from one another and very distinctive. We would then eat in for supper. The nearby village had an Intermarche, and there was a Leclerc hypermarket about 20 minutes away.
Overall, we enjoyed the holiday, but felt very fortunate not to have to endure a rainy day in a caravan.