Erin is always my favourite, she always chooses designs that suit both her and the mood of the dance. Off the floor, I think Camilla is always very stylish and never looks like she just got out of bed and threw on a track suit.
On the floor for the boys, I think Darren is usually well dressed, and doesn't show off too much chest (which, if you don't like that Ian/Brendan type of look can be a relief!). Off the floor, it's got to be the Don, Mr Anton Du Beke, ballroom dandy. I love a man that wears a tie for no good or practical reason.