Who Rocks Harder: Machine Head or DevilDriver??

Maybe it's not fair to pit two artists that are friends against one another, but who ever said metalheads play by the rules? There's no queston Machine Head and DevilDriver are two of Roadrunner Records' brightest lights and they both put out top-notch videos in 2007. Plus, they've both written awesome guest blogs for Headbangers Ball Blog (see Machine Head's here and DevilDriver's here).

But when you weight one against the other, there are definitely differences as well as similarities. While both have flirted with nu-metal in the past and are now pretty single-mindedly fixed on writing thrash and death-based songs that incinerate, Machine Head tend to take a more technical, multi-dimensional approach and DevilDriver go straight for the jugular. Yet even DD have a solid repertoire of atmospheric flourishes and heavy metal hooks that permeate the cranium-bashing beats. And while Machine Head can get melancholy or even (gasp) tender, they're also more than capable of heavy-duty quality brain-bashing. Both groups have a charismatic frontman seasoned from years of abuse in other bands (Machine Head's Robb Flynn in Vio-Lence, DevilDriver's Dez Fafara in Coal Chamber). And both stage monumentally intense live shows.

So you tell us, what does each band have that the other doesn't, and in the end, who rocks harder, Machine Head or DevilDriver?