When voting, do you choose the party or the person?

Tweet

Most people standing in most elections represent political parties. These people have little or no chance to influence the policies of the party they join. When required, they have to vote the way the party tells them to do so (known as whipping). So does the candidate matter since (s)he has little personal scope for expressing an opinion? Or would you rather vote for an independent candidate, like Martin Bell or the Jury Team candidates in the European elections? (s)he can vote according to his opinion and his voters' preferences. Which would you prefer?