l lookng at a new scotty cameron what is the difference between the scotty with 4 different colors on it and the 1 with 3 red dots

3 Red dots is the 2008 Model Studio Select.
4 colors is 2007 Model Studio Style.
2008 has no insert and feels slightly heavier, even though gram weight is identical.

If they are the same price, buy the newer model (3 dots). Last years should be discounted appropriately. It certainly is on E-Bay.