I don't think they've come even close, they just choose to stick to a certain style. Thats not a creative peak, at the moment they have no intention on doing an other concept album a-la V because Romeo himself says "it just takes to much fucking time" and after being on break for 5 years I'm sure that's not the path they want to take. Either or, everything Symphony X has done is in a league of its own, you can only compare it to its own. Which is still far above the rest, symphony x doesn't know the meaning of creative peak, after all they taught chuck norris the round house kick!
EDIT: Also to be noted, they found it much easier to tour with Paradise Lost (easy transition from album to live) where as some of there older stuff required some, or alot of rearranging. And to be fair, The Odyssey and Paradise Lost as albums are crowd favorites at live shows. I love the epic stuff, and its awesome live, but its not the same type of energetic performance. If I wanted to be bored to death watching them wank away on there guitars id go see Dream Theater. Actually thats a lie, Symphony X is never boring, but i digress!