The paper deals with an experimental comparison of a 4-approximation algorithm with a 3-approximation algorithm for the Shortest Common Superstring (SCS) problem. It has two main objectives, one is to show that even though the quotient between the two approximations is 4/3, in the worst case, the average results quotient is approximately 1, independently of the instances size. The second objective is to experimentally show that these algorithms produce high quality solutions, which are significantly lower than their guaranteed worst case bound.Most of the extensive computational experiments show that the algorithms produce an average superstring of length at most 1.4% over the optimum.