Well, i listened to all tracks:
Warning: Awesome;
The GIFT: Cute, i think i'll like it;
No future: It sounds nice and fun;
Out of control: It sounds nice too, but it was TOO short for me to have a good/bad impression;
Show must go on: It sounds fun, those "Yeah, yeah" (?) almost made me deaf lol;
Story: Seems pretty, but nothing special.
As for judging them only by short previews, well, i've had no problem doing this, since all my predictions were always right (for me), with the only exception being Terminal, but who knows, it might be a different case this time, let's just wait.