We've just got back from Whinfell Forest. The children loved it and not once did I hear the words 'I'm bored' and I found it so relaxing - after an awful, stressful week it was just what I needed. I now wish that we had gone when my older girls were little instead of dithering because I wasn't sure if we would like it (and I know some people really don't like it). It does seem to be a 'marmite' place by the reviews.
Anyway, needless to say we'll definitely book again! The children are already asking when we're going back :)