They are 70's rock evolved. As such, comparisons to other bands like Metallica and the forementioned Staind are errant in numerous ways. Not the least is the fact that trendiness is in no shape or form, or has been ever motivation for Tool. Tool has much more depth than any thing that Metallica has ever produced. Lateralus is the cleanest most powerful piece of music ever made.
Appreciation requires thought, something most people lack.