You can't keep everyone happy with the dance-off - there was such a fuss a few weeks ago when Jamelia lost out to NPP despite (according to us!) dancing better in the DO, but with Peter being a stronger contestant overall - but then this week when the stronger/more versatile dancer went out based on the DO alone and not her previous performances. Then there's people who say there shouldn't be a DO at all, but that's not a great solution either.
The judges choose one dance for the final and the contestants choose one, don't they? This has sometimes led to some odd choices, as sometimes the judges choose something they loved and want to see and give 40 to again, and sometimes it's something the couple didn't do great at which the judges want to see them improve, like Frankie's samba. I really hope they don't pick one of Katie's Latin dances, as it'll just be painful.