You may be shocked to hear this, but I didn't always like this couple. I had to do some simple logic just to figure out if Duncan should be with Gwen or Courtney. Thats when I knew this couple would work out perfectley.
Here are a few reasons why Duncan should dump Courtney and go with Gwen. First off, as the series progresses, you come to relise that Duncan can't stand Courtney and that he is becoming more fond of Gwen. Second of all, Gwen and Duncan have more in common. And third of all, Gwen doesn't seem to have any problem with Duncans Personality.
That is the whole reason I figured this couple will work.