i think that these two bands are very well known bands
I've never heard of either of them. I just looked them up, and I've still never heard of them. I'd look them up a second time, but that would probably make me have heard of them even less.
I think you chose two bands that are probably totally hyped where you live right now, but I too have to admit never have heard of them before you mentioning them here fries... =/
Next to that you should really be more extensive in your OP with these threads. Providing some background information and some examples for both bands (for those that don't know them) is the second step you want to take, the first would be to make a topic title that is less vague to those that don't know the bands. Just a friendly tip!
Never heard of these bands before, so I decided to look for one song of each band on YouTube. Why? That is uncertain. It's definitely not the kind of music I like. So based on just one song, I'd vote for Young Guns because their music is less noisy and I can tolerate it better.