My family and I have recently returned from a three week trip, where we stayed at La Garangeoire for a week (booked through Eurocamp). Based on our experience of this site I would have no problem in recomending it.
The site itself is part of the Castels group of Camp sites, and having stayed at two other Castels sites can say that they are very well organised and well run sites. The facilities are great, the two outdoor pools and waterslides were the favourite with our three children (Supervised by a Lifeguard and with no strict "no shorts" rules), the takeaway food was better than most campsites as some food was produced in the Restaraunt kitchen (namely the Pizzas and Salads) and were of reasonable quality. Although we never tried the Restaraunt food the Menu was very reasonable with a variety of dishes (of notable interest were the everchanging plats du jour). What I found best of all was the location, most Vendee sites tend to be clustered together on costal locations which tend to mean that the surounding areas and the sites themselves are get very busy and seemingly crowded, where as La Garangeoire is located in a quite country setting with a few close-by villages but still within easy driving distances of some of the great Vendee beaches and towns (La Sables, St. Giles within 20 Mins Drive, La Roche-sur-yon about 30 Mins). Another plus is the range of onsite activities, archery-Horse riding-Cycle Hire (7 euros a day for a very well maintained adult Mountain Bike)-Canoing on the large lake-fishing on one or two of the sites smaller lakes. Or you can still just get away from it all with a pleasent afternoon stroll on one, of about four, colour coded country walks that allow you meander through woods or fields and really appreciate the Vendee countryside and the size of the Site.
The pitches themselves are the biggest we have encountered and are well maintained as are the Toilet and shower blocks.
On the slightly negative side the pitch we had was, at our request, in a quite part of the camp, this placed us in a part of the camp at the base of a terraced slope next to a wood which meant we benefited from being more at one with Nature with regular vistits from Lizards, Toads, frogs, cheeky finches and, unfortunately the occasional Shrew and Mouse!. Although they would argue that they were there first. the only other slight citisism would be the number of children on bikes riding to fast round the park and without lights.
It is though, a park that I would gladly go back to.
Hope this helps.