Super fast reflexes, like spider sense.
Spend most of the week trying to avoid being punched (In a controlled environment) and you'll probably get that power.
That or speed, endurance, enhanced acrobatic/gymnastic abilities, slow the passage of time, foresight, etc
If it were a matter of preference, then foresight for definite, however, in terms of the Misfits universe, it'd be reflexes :/
Edit: Thats not personality, just realised.
Well I'm always thinking ahead, talking about the future, be it about bills, my work, my life, my plans. So yeah, foresight.
See? I got it in there
