I like the concept, but I always seem to have issues with these kind of tests that try to categorize you based on a fairly short questionnaire. In fact, I just took 3 different versions of the Big 5 test online and had some big variation in results:

• Consistently low on Neuroticism (range from 3-15)
• Consistently high on Openness (range from 93-100)
• Big range on Conscientiousness (28-54)
• Huge range on Extroversion (34-86, 2 were roughly same, one completely different)
• Huge range on Agreeableness (28-76, again, 2 roughly the same and one completely different)

The problem is that these scales are too simplistic, at least for me, and I'm sure for other people. So my score varies radically depending on the nature of the questions.

For example, I'm comfortable in any social situation, I don't mind being the center of attention, and I make friends easily. Extrovert, right? Except that, given a choice, I'd usually rather spend time alone than with people, and I'm perfectly happy talking to just one or two people at a party - I don't "make the rounds". So it totally depends on the specifics.

Conscientiousness? I'm very conscientious about commitments to other people when they're really depending on me, less so when it's just because I said I would do it, and I don't have what one would typically think of as rigorous self-disciplined. I'm actually very self-disciplined, just not in the typical way. I don't keep commitments just for commitment's sake, but when it really matters, I'm super-reliable.

My point is, I think these tools can be useful for self-exploration, but don't put too much weight into any one test or system. Human beings are complex -- YOU are complex -- and any test that has only 100 questions has questionable accuracy and probably isn't going to offer you any profound insights. And if you think it does, you might want to question it more deeply.