Integrating heterogeneous wireless networks invokes many architectural and technical challenges regarding networks cooperation, QoS and service continuity guarantees. In this paper, we focus on one of the main processes related to networks integration. It is the Vertical Handover (VHO), a critical process that requires high efficiency and low delays. We consider the Media Independent Handover architecture, proposed by the IEEE 802.21 working group in order to provide the required information for handover and mobility management entities. We propose an enhanced IEEE 802.21 Media Independent Handover framework (eMIH) that integrates a Vertical Handover Management Engine (VHME) for fast handover decision-making based on networks reputation, a new quality metric. It is a new cooperative indicator based on previous experiences and can insure higher efficiency and lower delays for vertical handover decisions in complex and rich environments such as integrated heterogeneous wireless networks.