I just listened to this disc 3 times through. If you like Styx or the AOR genre, it is definitely worth purchasing given that it can be obtained for a good price. The music is very diverse, so I can't imagine someone not finding something to enjoy. As others have mentioned, it is a fun album.
The surround mix is pretty good on most of the tracks. It is not a overly aggressive mix, but at different times harmony vocals, guitar and keys can be clearly heard coming from the rear channels. A nice balanced mix with nothing in the rear channels seeming out of place.
Some tracks are really excellent sounding. The ballads, "Yes I Can" and "Together" are excellent. The former in particular. It is simply a beautiful song.
Fortunately, the 5.1 tracks don't have the same level of "brightness" that the CD has. It is still a bit bright for my tastes, but not as bad as the CD. The 5.1 was mastered by a different person, which probably made a difference.
However, it is not perfect.... the drums sound poor throughout, IMO. The snare sounds kind of flat, and the cymbals are not really crisp. The rest of the instruments sound quite good, so it is probably just how the drums were recorded. Perhaps this is a personal preference.
I give an 8 on all counts; mix, fidelity and content.