I think most 'normal' people would take the grey route - the Jedi are too aloof, and their suppression of all emotion is something which comes across as alienating. My personal faves are Qui-Gon and Jolee - both mavericks, both considered grey, but far more genuine as people than many of the ivory tower Jedi who stick to the code and the council as mantra. Jolee walks the balance between the two sides very easily indeed - there is no malice or risk of falling in him, but plenty of emotion.
Of course, if the choice is simply between the two, then it's LS every time. Helping people is a much more natural urge than destroying them, and more rewarding as well - DS can lead only to domination, and even if you got to the very top your reign would not be peaceful, as that is the nature of the beast. You'd have to be inhuman to cope with your actions, and that isn't really a price worth paying.