They are headlining Keep it True though.
Yes, in Germany (and I'll be at that show
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). In the US, however, they're a mid tier band.
The thing with all of these suggestions is that the how many albums a band has out, or their status in the underground, or their status in Europe has very little to do with how succesful they would be as a PPUSA headliner.
The main criteria for being a headliner is the ability to put asses in the seats.
Jag Panzer? The last time they played a headlining set here, I saw them play to under 50 people. Sure they've got a lot of great albums, and a great history, but few people in the US care about them.
Manowar? They cetainly have a devoted fan base, but it's not huge. Yeah, they're bigger in Europe, but here, they just don't draw well.
Crimson Glory? Well, they've got the history for sure.... and 8 years (and counting) since their last disc. Even with a sober Midnight, I can't see them being any bigger than Conception - and they only got a direct support slot.
ARK? Let's just say the singer is not the issue there
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With only two albums out, they're a #4 slot (ala, Conception) at best.