Thermal conductance and loss of pressure are among the most relevant parameters based on which a heat exchanger has to be chosen. Starting from this observation this study treated and compared the performances of different exchanging systems, always in condition of forced convection of air in laminar flow. The study parameters were two fin shapes, four modules (shapes), and four duct geometries (depending on the parameter shape ratio, defined in Sec. 3). The approach chosen was that of Bejan’s Constructal theory numerically implemented by the finite element code COMSOL MULTIPHYSICS . The results showed the importance of considering not the heat removing performance alone as a decisional parameter and proved that the “classic” I-shaped finned systems very often are not the best performing ones, while optimized Y profiles may offer better perspectives. Having demonstrated the relevance of the present approach, future developments of this research will have to put together the different evaluation criteria presented in an only performance parameter.