Their most polished albums are Purgatory Afterglow and Crimson I & II. Note that the rest of the band did not play on Crimson II, Edge's last last album. Dan brought in a bunch of ringers and has a proggier feeling, and it has the best studio quality of all their albums.
Nothing But Death Remains would be their rawest work; production is kind of messy, and would not recommend it until you develop a taste for the band. Infernal is also risky; there are some great songs, but Dan was about to leave the band when it recorded and it's reflected in the big disparity between songs that Dan wrote and the ones his bandmates put together. Cryptic, the Dan-less EoS album, is pretty bad. Disappointing is a good word for it, since Dread's songs on Infernal have a Hypocrisy-type sound to it and the album should have been better (the guitars on that album blow).
Spectral Sorrows, Unorthodox, Until Eternity Ends... all highly recommended. Unorthodox is fucking brutal. Their best album, imo, is Purgatory Afterglow. Twilight and Black Tears are EoS' two best songs.
I'd start with Purgatory Afterglow, Crimson I & II, then work my way through Spectral Sorrows, Unorthodox and Until Eternity Ends. Probably Infernal after that, and if you like the band, Nothing But Death Remains is an interesting listen. I'd just download Cryptic off the net if you're curious. Dan doesn't give a shit about you downloading his music (I'm quoting him on that), and he probably doesn't get any royalties from that album anyway.
And of course, buy Moontower. Now. Purchase that shit. That's Dan's prog-death metal side project. You can also download an EoS version of Uncreation from his Moontower project off his website, which is really fucking good.
If you can't get enough of Dan after that, then go for his Nightingale and Unicorn stuff. Highly recommend Nightingale's most recent two albums. On the newest Dan re-recorded Losing Myself from Infernal, so you might want to check that out, too. =)
