This is how I look at it. The word is specific to the Black American culture. Although it's roots are in slavery it has taken on a new meaning and is used within the community as a term of endearment. I tend to see it as being similar to words in other cultures that create a sense of camaraderie such as "pare" in Tagalog, "uso" in Samoan or "carnal" in Spanish. So, in my opinion, if you've been accepted into the community and the word has been used toward you, then I feel it is ok to use the word in return. However, this doesn't mean that one can use it freely outside of the community or with members of a different culture. So yeah, keep it within the black community.
What would you think if you saw two white guys referring to each other as "pare."