Achieving Bullet Holes

What would be a good way to create bullet holes/marks on a wall. I've seen people use decals and raycasting. Also, on the Unity3D manual/reference thing, they said projectors could be used for bullet holes. I want to go with a projector because I want bullet holes look better on round objects. What would you reccomend, and how would I achieve this?

Thanks in advance :)

A projector is not a good idea for bullet holes, since it redraws the entire object that it's projecting the texture onto. Therefore several dozen bullet holes would have a large negative effect on the framerate. Go with raycasting and decals.