People here seem to underrate Shin a lot. First of all he has sharingans all over his head, giving him a 360 degree vision, with the previliges of the sharingan predicting the enemy's attack. He was able to go against Sasuke in a mini clash, and can send weapons from behind Yamato's back, meaning that he won't be able to see them. He has furthermore showed amazing durbility, surviving after Sakura directly punched hum. Shin's weapons were also strong enough to pierce through Naruto's chakra cloak, and Shin's clone. Overall i would say that Shin is around high jounin level of power by his feats, and might be able to defeat Yamato with high difficulties.