No preference, though I don't get to run evil characters since my group hasn't done an evil campaign since I joined them (only time they did was when I was DMing). I'll usually play a different alignment to last time when I switch to a new character.
And to answer BlackSilver's original question, that has nothing to do with my view of the world and the way I live my life. I've got a very ironclad and idiosyncratic set of values I came up with and am the most consistent person I know. I've played a character with the same values and approach to life once, and enjoyed it throughly, but every other PC of mine has been very different.