Pendants like this can be set so that they do not flip. It is a question of the placement of the d-rings. I have a heart diamond set similarly and it does not flip.
Some like the marquise shape and some don't. It does not look like an eye to me. I don't know that it would poke since the sharp points would not be directly on your neck. The questions are, do you like it? Have you seen it on you? and, if you are not sure, is there a good return policy (no questions asked, reasonable amount of time?)
It would be unusual. do you go for the unusual/unique or are you one who prefers to wear what everyone else is wearing? There is no right or wrong answer to this question, nothing is wrong with either personality type but it's good to know who you are and what you will end up liking.
Best of luck deciding. I think this could be gorgeous and flattering but cannot tell you if YOU will like it.