Two years previously I visited Mutianyu section. Because Mutianyu is much quieter I was shocked by the vast amount of Chinese tourists there were beetling their way up the wall.
The climb is steep but reasonably short. Worth it for the view though!
If you can get yourself there without a guide I'd advise you to do so. Organised tours that offer Ming Tombs, Great Wall, Silk factory all in a day etc will over charge on everything where possible. Bring water and food with you too. Food is comparatively expensive there and only small snacks are available. In the summer it will be scorching too so bring whatever you need to deal with that.
The downside is the huge crowds. The entrance road is too narrow for the coaches that were trying to arrive by the hundred. Eventually we got out and walked along the side of the highway to get there. Those hundreds of coaches turn into thousands of people, all shoving there way through the bottle necks of the wall's steeper parts. Towards the top though the crowds thin.
Overall a pleasant experience but there's no point in coming here when Mutianyu has a cable car if you would like, is wider, meaning no one is jacking anyone elses photos and the best bit - it;s FAR less busy.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC