Opinions on Dream Theater's Meta album?

I've been so hooked on Dream Theater for the past few months now. I really can not stop listening to each and every one of their albums... After looking up information on both the band and the music they write, I am absolutely fascinated by the work that they've done and their accomplishments. One thing that I am most fascinated by is their meta album, which some of you may not be aware exists. It is made up of Metropolis Part 2: Scenes from a Memory, Six Degrees of Inner Turbulence, Train of Thought, and Octavarium (in that order). These 4 albums are all linked together and you'll notice that the end of each album leads into the beginning of the next album. I think this concept is just amazing. It's comprised of over 5 hours of music and I can not stop listening to it. Was anyone else aware of this and if so, what are your opinions?