What are the best albums by Avantasia/Dream Theater?

A friend of mine recently made me listen to The Scarecrow by Avantasia and Falling into Infinity by Dream Theater. I would follow his advice on the best albums but he isn't much help and said they're all amazing. I would just like to know some of their best albums or songs, as I don't want to listen to duds which will put me off them. Any help is appreciated.





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5d theater
5d theatre