Both of these sets are fantastic!! I have made all 6 dinosaurs now. The Panoplosaurus and the Ankylosaurus take the most time and are the most advanced, but I wouldn't call them "difficult." Just take more time and patience. However, they turn out so awesome that it's worth it. My favorite ended up being the Protoceratops. I love the way his head fin is constructed. He's very simple, but looks fantastic. Highly recommend all of June's dino patterns.