Just got back from our 2nd trip to Le Letty, having stayed there last year too. We've also recommended it to our friends, some of whom stayed before us this year (and loved it) and others who were there same time as us. And whilst there, we recce'd other fields to decide where we'd like to camp next year if we went again...
You can't fault the campsite...amazingly spotless. Intimate little fields and largely friendly neighbours amongst the campers, even with a language barrier at times! Fantastic pool and a great beach front with an estuary that because of the tide is different every time you visit.
It's only 20 mins walk to the restaurants of Benodet for a night out, but mostly we ate what we cooked. There's a takeaway and it's ok but not great. The shop is well-stocked and has a bakery for the morning baguette/croissant/pain-au-chocolat fix.
The only problem for us was the rain. We had a stunning first week of sunshine and had no problems coaxing the kids down to the sea and away from the pool. The 2nd week was much wetter, some fairly heavy downpours both during the day and the night. Which meant trips to the indoor pool, pretty much like everyone else on site, which wasn't my cup of tea but the kids seemed to enjoy it. So if they could just bust the clouds away to keep the sun shining, it would be perfect.