Gravity kills is kindof industrial.... I've heard their songs a few times; I would try turning off the speaker emulators completely and maybe using a hint of chorus. (Although I really don't like the chorus they use on the POD that much).
I'm still learning w/ the POD, too. I'm not sure whether I like going through the clean channel w/ my DOD Death Metal pedal, or using the Line 6 Insane. Oh, the decisions... desicions...