The Syndicate

A few staples have been in here for years (in some cases a decade!) but the list has really changed over time, some have fallen, been dropped entirely, while some have moved on in:

1. Symphony X

2-5: Opeth, Agalloch, Isis, Godspeed You! Black Emperor

6-10: System of a Down, Megadeth, Tool, King Crimson, Pelican

That was tough, there's so many I love but pretty much I picked bands (generally) with large discogs that I like a lot to all of, that I can listen to anytime, that I've not grown tired of over time, and especially if they can sometimes send me off to that place music can take you...
Honorable mention: Maudlin of the Well, Nevermore, Atheist, Pain of Salvation, Russian Circles