Due to the ever-increasing traffic demands and the fact that the spectrum resources are limited, it is very likely that several secondary networks (SNs) will coexist and opportunistically use the same primary user (PU) resources. In such coexistence scenarios, it is fundamental to guarantee fairness among the coexisting SNs. To that end, in this paper, we evaluate the performance of an SN coexistence scheme in terms of fairness and we show that it can achieve throughput and energy efficiency gains, while maintaining fairness among the coexisting SNs in comparison to other state-of-the-art approaches.