I don't know what type of bushings came stock on your bike (if any did at all), but I would recommend using polyurethane bushings. They are an upgrade from a softer rubber type that is sometimes used. They are the most popular type of bushing and in my opinion, provide just the right amount of 'give' and provide a solid feel.
2008 Night Rod Special
2010 Dyna Fatbob (HDforums member)