TSO are a great band. Excellent idea, combining classical and metal together, and it really works well. I reviewed "Night castle" in my journal (you can read the review here
http://www.musicbanter.com/members-j...ml#post1104468
Personally though, if I had to choose one Savatage album that links them and TSO it would be "The wake of Magellan", on which I think they began to move away from the overt rock and metal and more towards a progressive style that would eventually result in the formation of TSO.