I saw a Dutch hardcore band supporting Comeback Kid. They were called No Turning Back and were quite good.
Coheed are prog-rock but they're incredible, anybody who says otherwise is wrong! They're pretty geeky too (there's also comics/graphic novels that the albums are based on as they're all concept albums telling a story).
Soulfly, Lamb of God, Sylosis and In Flames are all good too. I like old Machine Head (plus the Blackening which was ace), Killswitch Engage, One Minute Silence, Slipknot and others when it comes to metal (I have quite diverse music tastes from Ska to Hardcore!)