Freuder defined interchangeability for classical Constraint Satisfaction Problems (CSPs). Recently, we extended the definition of interchangeability to {em Soft} CSPs and we introduced two notions of relaxations based on degradation $delta$ and on threshold $alpha$ interchangeability. In this paper we study the presence of these relaxed version of interchangeability in random soft CSPs. We give a description of the implementation we used to compute interchangeabilities and to make the tests. The experiments show that there is high occurrence of $alphaNI$ and $deltaNI$ interchangeability around optimal solution in Fuzzy CSP and weighted CSPs. Thus, these algorithms can be used succesfully in solution update applications. Moreover, it is also showed that $NI$ interchangeability can well approximate $FI$ interchangeability.