Best: I know this is just Civilian but CBB4's twist with Chantelle having to lie about being in a girl band to become a housemate is classic. Best twist. Ever. Makosi's unlucky thirteen twist was also FANTASTIC. Best civilian twist. It was good seeing Makosi having to create all the drama in the house but we found out she was just like that anyway
I think it shows the simpler the twists the better.
Worst: BB12's was just. I can't even put it into words. The whole Pamela Anderson thing and it just felt so so so tacky. Definitely worst twist for me. (BB7 and BB10 had pretty crap launch night twists also)