Pagan's Mind is pretty good, but when I'm looking for prog metal that's more or less paint-by-numbers but well done I usually go for Vanden Plas. They have some great melodies and solid riffs.
Symphony X are the kind of band you love when you first hear them and then get bored with after three months. I went through that phase about three years ago, and as a result I have nearly their entire disco that I rarely listen to sitting on my shelf. V is far and away their best, so get that one if you're looking for something by them. The Divine Wings of Tragedy has two amazing epics (title track and Accolade) and a lot of generic SymX rockers. The Odyssey is hugely overrated and basically a worse version of TDWOT with awful production, so I don't recommend it. Paradise Lost is fine if you just want well-done power/progressive metal without much originality, and Twilight in Olympus is good if you need more SX but not something you really need otherwise. The first two albums aren't all that good and the live album has unlistenable production, so avoid them.
