often messy and frustrating , but very pleasing at its best moments 
(ROOT (ADJP (ADJP (RB often) (JJ messy) (CC and) (JJ frustrating)) (, ,) (CC but) (ADJP (RB very) (JJ pleasing)) (PP (IN at) (NP (PRP$ its) (JJS best) (NNS moments)))))
(ROOT (ADJP (ADJP (RB ) (JJ ) (CC ) (JJ )) (, ) (CC ) (ADJP (RB ) (JJ )) (PP (IN ) (NP (PRP$ ) (JJS ) (NNS )))))