I believe more is accomplished with collaboration, so I am more apt to support it over competition. I enjoy competition but I feel it is best left up to sports and games, where collaboration is better for all other uses. They are both helpful ideals but they should have their place.
Playing the human race game as a zero sum equation might end up with one "winner", but history shows that winners don't fare well when the angry mob comes knocking with torches and pitchforks. Only through collaborative action are we likely to ever move forward as a species. Senseless
competition only leads to waste and inefficiency.
I support competition over collaboration. Collaboration is just something that will always end up in people become complacent and stop doing their best. The only way to really improves is to be in direct competition with others as this will push you beyond your current limits to become much better.
Humans respond better to competition than collaboration in most settings. The best example I can think of is the economic systems of Capitalism versus Communism. (True) Capitalism gives people motivation through competition while Communism in its most pure form lowers standards and kills creative thought and work drive. The best example of this is in the Soviet Union, when no one wanted to be a Doctor in the 1980s.
I support competition over collaboration, because competition allows the best to win. If a person knows that they have to compete in order to get ahead, they are more likely to try harder. Competition gives people an incentive to achieve. Working in a group, some people are certain to slack. Competition brings out the best.