Coming in on the 7th disc of a band's career makes it a weird position to write a review from. After all, what I think is great may in fact just be a retreading of the past 10 years of their career. On the other hand, if it sounds good, does that really matter? It just means they have a long back-catalog of equally good music.
That's neither here nor there, I suppose.
Eidolon is a side project of Shawn and Glen Drover, drummer and guitarist respectively with Megadeth; The Parallel Otherworld marks the arrival of vocalist Nils K. Rue of Pagan's Mind. Eidolon's music falls more along the lines of progressive metal, with lots of keyboard textures and more of the Dream Theater-styled, pseudo-operatic vocals. In fact, the opening track is an 11-minute epic that sets up pretty much everything else you're going to hear on the disc--thrashy riffing, piano and key textures, an acoustic passage, and shredding. Ah yes, the shredding, which fortunately features more prominently in later songs than the relatively short section I recall on the opening track.
So yeah, maybe The Parallel Otherworld is just more of the same. On the other hand, even if that's the case, it still means it's quite enjoyable hour-long trip through prog metal staying close to thrash roots. Definitely a worthwhile release, give it a shot.