I think they're great.
I've just listened to the other singles on the internet.
The standard of singles is so high. I like 'Hook Me Up' best, but I dont know if it would be better for Autumn, so they could release 'Take Me On The Floor' second as a summer single, and then release 'Hook Me Up' in about September - plus its a school themed video, which would go well for people returning to school in september.
'This Love' is a ballad, so they might release it 3rd, but other artists like Katy Perry, who is similar to them, didn't really have successful ballad singles.