Overall musicianship, creativity, song structure, lyrics that actually have substance (especially for the main genre they fall under), their randomness in songs that seems to work even though you think it wouldn't when hearing about it, vocals (I love the sound between death metalish vocals and the clean vocals), Paul Waggoner being more then likely one of the best progessive metal guitarists out these days.
Plus they are amazing live. They sound damn near dead on to how they do on their albums.
I think most of us are listening to the same band, guess you just don't hear what we do which happens sometimes. As an example almost everyone on here loves Chevelle minus me, I just don't hear what's so great about them and probably never will.