I prefer a contract job. I'm doing it since1992.
But anyhow, the question here is not really balanced. In fact this question should be divided into2 questions. Do you prefer a contract job, or being employed by a employer.
the2nd question is, do you prefer a part-time job or full-time.
I will prefer any job between contract / full time. This job may or may not be in my Domain expertise but the most important thing is that it should allow me to work innovatively and should give space to implement the new concepts.