Is the anti-conformist really more of an individual than the conformist? I think not. The anti-conformist prides himself on not being a slave of trends. But instead, he is a slave to anti-trends: he must not do whatever is currently popular. Thus, he is little different than a conformist, he cannot think for himself.
This does not means we should not be skeptical of mainstream ideas or behaviors, or that the principled rejection of them is uniformly bad. Instead I only wish to point out that the uninformed rejection of ideas because of their source can be counterproductive to one's aims. Overuse of the word "never," it may get you into trouble by taking away important options.
A common manifestation of this problem is overcompensation: the parent, eg, who says "I'll never be like my parents!" and in the process is far worse. We may now have a president who tries a bit too hard to not be like his dad, distorting his policy decisions. Or think of the nihilistic Berkeley activists, who would seem to oppose anything anyone with power would attempt to implement, regardless of their merits.
Being able to make your own judgements highly desirable -- I will write more on this later. Just be careful: rejecting the judgements of others does not necessarily mean that you have judged for yourself.