If you are curious about what having a shaved head is like, the itch won't go away until you try it. Buzz down to a 0. That'll give you a good idea of what you'll look like. The real difference between a 0 and fully shaved is in how it feels. And as we'll all tell you, the shaved feeling is great - and incredibly addicting.
If you do go down to a 0 and don't like it, you won't have to live with it very long. In a week or two your hair will have grown out to a 2.