To me it makes little difference whether the band is "Christian" or not. What matters, imo, is whether the music is uplifting and reinforcing to the spirit, or whether it drags you down. I have a problem with most of the Christian bands I've come across (see my post "Christian Music - Cloning?")
Also, most Christian bands I've found are afraid to delve into the darker aspects of human life. I don't think there's anything wrong with writing an angry song, or a "depressing" one, because art (to me) is supposed to encompass all of the aspects of life. We all go through dark times; it's healthy to write in your journal about it, it's not healthy to pretend it's not there. That's called suppression, or the stuffing down of emotions.
However, if you're running in the same self-destructive circle, it's obviously not doing any good. There has to be a progression. This is why I love progressive music...not just progression or change within a song, but within an album, and even a development from album to album.
Hence why I love both Tool and Nine Inch Nails. Both refined their sound between releases (though Tool is the more progressive of the two). Though NIN's nihilistic concepts remained present throughout most of their music, it still felt cathartic. It was all dark, but it moved from self-hate to depression to attempting to move out but feeling trapped. Finally, Trent Reznor found his peace and got married and quit using drugs.
Also, it's a matter of interpretation. Many people feel dark music has some kind of subconscious power to poison the mind. This may be true if you're feeding into it, but when I listen to Nine Inch Nails, I actually feel hope...it's a reminder of how far I've come, where I was once and where I am now.
I've listened to P.O.D., blindside, project 86, Skillet, Pillar, Eternal Decision, Disciple, Demon Hunter...the list goes on. I'm not impressed with any of them. Keep in mind that I'm also not impressed with most secular music, including Sevendust. I've also got a very specific viewpoint that not everyone really understands (or they simply have their own). That being said, you can check out the bands I listed and you may like them.
Dave Mustaine apparently became a Christian a while ago. He's the leading force in Megadeth, and I like a lot of their stuff.
Just because you may disagree with someone doesn't mean they don't have something good to say.
Bands I'm impressed with:
Tool and NIN.
A Perfect Circle.
Puscifer (check out "Sour Grapes" on youtube)
Alice in Chains
Metallica (before 1990)
Megadeth
Korn (first three albums)
Rage Against the Machine
Audioslave
Rush
Pantera (RIP Dimebag)
Primus
Opeth
Each has a unique sound, talks about meaningful stuff (though Pantera's vocalist doesn't seem all that intelligent), and contributed greatly to music. And all of them, in their own way, inspire me to be a better person, some in ethical ways, some in emotional, and some in spiritual (mainly Tool).
That's my view, anyways.
Oh yeah, and the "Christian" title doesn't always mean much...after all, Tim Lambesis (As I Lay Dying's front man) is in jail for trying to hire an undercover cop to murder his wife. Then he blamed in on the steroids he's been taking. I assume he blames the steroid for having another girlfriend on the side, too.